diff --git a/rtengine/CMakeLists.txt b/rtengine/CMakeLists.txt
index c50abb88c..01424543b 100644
--- a/rtengine/CMakeLists.txt
+++ b/rtengine/CMakeLists.txt
@@ -145,6 +145,7 @@ set(RTENGINESOURCEFILES
     lj92.c
     lmmse_demosaic.cc
     loadinitial.cc
+    metadata.cc
     munselllch.cc
     myfile.cc
     panasonic_decoders.cc
diff --git a/rtengine/imagedata.cc b/rtengine/imagedata.cc
index 1977061db..e7cf2b4c2 100644
--- a/rtengine/imagedata.cc
+++ b/rtengine/imagedata.cc
@@ -22,11 +22,11 @@
 #include <tiff.h>
 #include <glib/gstdio.h>
 #include <glibmm/convert.h>
-#include <exiv2/exiv2.hpp>
 
 #include "imagedata.h"
 #include "imagesource.h"
 #include "rt_math.h"
+#include "metadata.h"
 #include "utils.h"
 
 #pragma GCC diagnostic warning "-Wextra"
@@ -52,24 +52,6 @@ namespace rtengine {
 
 extern const Settings *settings;
 
-Exiv2::Image::AutoPtr open_exiv2(const Glib::ustring& fname)
-{
-#ifdef EXV_UNICODE_PATH
-    glong ws_size = 0;
-    gunichar2* const ws = g_utf8_to_utf16(fname.c_str(), -1, nullptr, &ws_size, nullptr);
-    std::wstring wfname;
-    wfname.reserve(ws_size);
-    for (glong i = 0; i < ws_size; ++i) {
-        wfname.push_back(ws[i]);
-    }
-    g_free(ws);
-    auto image = Exiv2::ImageFactory::open(wfname);
-#else
-    auto image = Exiv2::ImageFactory::open(fname);
-#endif
-    return image;
-}
-
 } // namespace rtengine
 
 FramesMetaData* FramesMetaData::fromFile(const Glib::ustring& fname)
@@ -106,9 +88,9 @@ FramesData::FramesData(const Glib::ustring &fname) :
     lens.clear();
 
     try {
-        auto image = open_exiv2(fname);
-        image->readMetadata();
-        const auto& exif = image->exifData();
+        Exiv2Metadata meta(fname);
+        meta.load();
+        const auto& exif = meta.exifData();
         ok_ = true;
 
         // taken and adapted from darktable (src/common/exif.cc)
@@ -189,7 +171,7 @@ FramesData::FramesData(const Glib::ustring &fname) :
 
     /*
     TODO: Implement ratings in exiv2 situations. See PR #5325
-        
+
     // Look for Rating metadata in the following order:
     // 1. EXIF
     // 2. XMP
diff --git a/rtengine/imagedata.h b/rtengine/imagedata.h
index f692d4267..b1a29dc39 100644
--- a/rtengine/imagedata.h
+++ b/rtengine/imagedata.h
@@ -22,8 +22,6 @@
 #include <memory>
 #include <string>
 
-#include <exiv2/exiv2.hpp>
-
 #include "imageio.h"
 
 namespace Glib
@@ -36,8 +34,6 @@ class ustring;
 namespace rtengine
 {
 
-Exiv2::Image::AutoPtr open_exiv2(const Glib::ustring &fname); // TODO: Global function?
-
 class FramesData final :
     public FramesMetaData
 {
diff --git a/rtengine/imageio.cc b/rtengine/imageio.cc
index 26ea87a44..475792e83 100644
--- a/rtengine/imageio.cc
+++ b/rtengine/imageio.cc
@@ -79,39 +79,7 @@ FILE* g_fopen_withBinaryAndLock(const Glib::ustring& fname)
 
 }
 
-MetadataInfo::MetadataInfo(const Glib::ustring& src) :
-    src_(src),
-    exif_(new rtengine::procparams::ExifPairs),
-    iptc_(new rtengine::procparams::IPTCPairs)
-{
-}
-
-const Glib::ustring& MetadataInfo::filename() const
-{
-    return src_;
-}
-
-const rtengine::procparams::ExifPairs& MetadataInfo::exif() const
-{
-    return *exif_;
-}
-
-const rtengine::procparams::IPTCPairs& MetadataInfo::iptc() const
-{
-    return *iptc_;
-}
-
-void MetadataInfo::setExif(const rtengine::procparams::ExifPairs &exif)
-{
-    *exif_ = exif;
-}
-
-void MetadataInfo::setIptc(const rtengine::procparams::IPTCPairs &iptc)
-{
-    *iptc_ = iptc;
-}
-
-void ImageIO::setMetadata(MetadataInfo info)
+void ImageIO::setMetadata(Exiv2Metadata info)
 {
     metadataInfo = std::move(info);
 }
@@ -1181,9 +1149,9 @@ int ImageIO::saveTIFF (const Glib::ustring &fname, int bps, bool isFloat, bool u
     TIFFSetField (out, TIFFTAG_SAMPLEFORMAT, (bps == 16 || bps == 32) && isFloat ? SAMPLEFORMAT_IEEEFP : SAMPLEFORMAT_UINT);
 
     /*
-    
+
     TODO: Re-apply fix from #5787
-    
+
     [out]()
     {
         const std::vector<rtexif::Tag*> default_tags = rtexif::ExifManager::getDefaultTIFFTags(nullptr);
@@ -1388,32 +1356,34 @@ bool ImageIO::saveMetadata(const Glib::ustring &fname) const
     }
 
     try {
-        auto src = open_exiv2(metadataInfo.filename());
-        auto dst = open_exiv2(fname);
-        src->readMetadata();
-        dst->setMetadata(*src);
-        dst->exifData()["Exif.Image.Software"] = "RawTherapee " RTVERSION;
-        for (const auto& p : metadataInfo.exif()) {
-            try {
-                dst->exifData()[p.first] = p.second;
-            } catch (const Exiv2::AnyError& exc) {
-            }
-        }
-        for (const auto& p : metadataInfo.iptc()) {
-            try {
-                auto& v = p.second;
-                if (!v.empty()) {
-                    dst->iptcData()[p.first] = v[0];
-                    for (size_t j = 1; j < v.size(); ++j) {
-                        Exiv2::Iptcdatum d(Exiv2::IptcKey(p.first));
-                        d.setValue(v[j]);
-                        dst->iptcData().add(d);
-                    }
-                }
-            } catch (const Exiv2::AnyError& exc) {
-            }
-        }
-        dst->writeMetadata();
+        metadataInfo.load();
+        metadataInfo.saveToImage(fname);
+        // auto src = open_exiv2(metadataInfo.filename());
+        // auto dst = open_exiv2(fname);
+        // src->readMetadata();
+        // dst->setMetadata(*src);
+        // dst->exifData()["Exif.Image.Software"] = "RawTherapee " RTVERSION;
+        // for (const auto& p : metadataInfo.exif()) {
+        //     try {
+        //         dst->exifData()[p.first] = p.second;
+        //     } catch (const Exiv2::AnyError& exc) {
+        //     }
+        // }
+        // for (const auto& p : metadataInfo.iptc()) {
+        //     try {
+        //         auto& v = p.second;
+        //         if (!v.empty()) {
+        //             dst->iptcData()[p.first] = v[0];
+        //             for (size_t j = 1; j < v.size(); ++j) {
+        //                 Exiv2::Iptcdatum d(Exiv2::IptcKey(p.first));
+        //                 d.setValue(v[j]);
+        //                 dst->iptcData().add(d);
+        //             }
+        //         }
+        //     } catch (const Exiv2::AnyError& exc) {
+        //     }
+        // }
+        // dst->writeMetadata();
         return true;
     } catch (const Exiv2::AnyError& exc) {
         std::cout << "EXIF ERROR: " << exc.what() << std::endl;
diff --git a/rtengine/imageio.h b/rtengine/imageio.h
index 3283d5816..26e7164e6 100644
--- a/rtengine/imageio.h
+++ b/rtengine/imageio.h
@@ -24,6 +24,7 @@
 #include "iimage.h"
 #include "imagedimensions.h"
 #include "imageformat.h"
+#include "metadata.h"
 #include "rtengine.h"
 
 enum {
@@ -52,25 +53,6 @@ class ColorTemp;
 class ProgressListener;
 class Imagefloat;
 
-class MetadataInfo final
-{
-public:
-    explicit MetadataInfo(const Glib::ustring& src = {});
-
-    const Glib::ustring& filename() const;
-
-    const rtengine::procparams::ExifPairs& exif() const;
-    const rtengine::procparams::IPTCPairs& iptc() const;
-
-    void setExif(const rtengine::procparams::ExifPairs &exif);
-    void setIptc(const rtengine::procparams::IPTCPairs &iptc);
-
-private:
-    Glib::ustring src_;
-    std::unique_ptr<rtengine::procparams::ExifPairs> exif_;
-    std::unique_ptr<rtengine::procparams::IPTCPairs> iptc_;
-};
-
 class ImageIO : virtual public ImageDatas
 {
 
@@ -84,7 +66,7 @@ protected:
     MyMutex imutex;
     IIOSampleFormat sampleFormat;
     IIOSampleArrangement sampleArrangement;
-    MetadataInfo metadataInfo;
+    Exiv2Metadata metadataInfo;
 
 private:
     void deleteLoadedProfileData( );
@@ -124,7 +106,7 @@ public:
     cmsHPROFILE getEmbeddedProfile () const;
     void getEmbeddedProfileData (int& length, unsigned char*& pdata) const;
 
-    void setMetadata(MetadataInfo info);
+    void setMetadata(Exiv2Metadata info);
     void setOutputProfile(const std::string& pdata);
 
     bool saveMetadata(const Glib::ustring &fname) const;
diff --git a/rtengine/improccoordinator.cc b/rtengine/improccoordinator.cc
index 804e81ac0..b74a137ff 100644
--- a/rtengine/improccoordinator.cc
+++ b/rtengine/improccoordinator.cc
@@ -31,6 +31,7 @@
 #include "image8.h"
 #include "imagefloat.h"
 #include "improcfun.h"
+#include "metadata.h"
 #include "labimage.h"
 #include "lcp.h"
 #include "procparams.h"
@@ -320,7 +321,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
         RAWParams rp = params->raw;
         ColorManagementParams cmp = params->icm;
         LCurveParams  lcur = params->labCurve;
-        
+
         if (!highDetailNeeded) {
             // if below 100% magnification, take a fast path
             if (rp.bayersensor.method != RAWParams::BayerSensor::getMethodString(RAWParams::BayerSensor::Method::NONE) && rp.bayersensor.method != RAWParams::BayerSensor::getMethodString(RAWParams::BayerSensor::Method::MONO)) {
@@ -528,8 +529,8 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                         lastAwbauto = "";
                         autoWB.useDefaults(params->wb.equal);
                     }
-                    
-                    
+
+
                 }
 
                 currWB = autoWB;
@@ -542,11 +543,11 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
 
             if (autowb && awbListener && params->wb.method ==  "autitcgreen") {
                 awbListener->WBChanged(params->wb.temperature, params->wb.green, studgood);
-            } 
+            }
 
             if (autowb && awbListener && params->wb.method ==  "autold") {
                 awbListener->WBChanged(params->wb.temperature, params->wb.green, -1.f);
-            } 
+            }
 
             /*
                     GammaValues g_a;
@@ -748,7 +749,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                 whiteev = new float[sizespot];
                 bool *Autogr = nullptr;
                 Autogr = new bool[sizespot];
-                
+
                 float *locx = nullptr;
                 locx = new float[sizespot];
                 float *locy = nullptr;
@@ -761,7 +762,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                 centx = new float[sizespot];
                 float *centy = nullptr;
                 centy = new float[sizespot];
-                
+
                 for (int sp = 0; sp < sizespot; sp++) {
                     log[sp] = params->locallab.spots.at(sp).explog;
                     autocomput[sp] = params->locallab.spots.at(sp).autocompute;
@@ -865,7 +866,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
       //  if ((todo & (M_LUMINANCE + M_COLOR)) || (todo & M_AUTOEXP)) {
         //    if (todo & M_RGBCURVE) {
         if (((todo & (M_AUTOEXP | M_RGBCURVE)) || (todo & M_CROP)) && params->locallab.enabled && !params->locallab.spots.empty()) {
-            
+
             ipf.rgb2lab(*oprevi, *oprevl, params->icm.workingProfile);
 
             nprevl->CopyFrom(oprevl);
@@ -964,7 +965,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                 const bool llmaslogutili = locllmaslogCurve.Set(params->locallab.spots.at(sp).LLmaskcurveL);
                 const bool lcmaslogutili = locccmaslogCurve.Set(params->locallab.spots.at(sp).CCmaskcurveL);
                 const bool lhmaslogutili = lochhmaslogCurve.Set(params->locallab.spots.at(sp).HHmaskcurveL);
-                
+
                 const bool lcmas_utili = locccmas_Curve.Set(params->locallab.spots.at(sp).CCmask_curve);
                 const bool llmas_utili = locllmas_Curve.Set(params->locallab.spots.at(sp).LLmask_curve);
                 const bool lhmas_utili = lochhmas_Curve.Set(params->locallab.spots.at(sp).HHmask_curve);
@@ -1053,7 +1054,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                 int xxe = xend * ww;
                 int yys = ysta * hh;
                 int yye = yend * hh;
-                        
+
                 if(istm) { //calculate mean and sigma on full image for RT-spot use by normalize_mean_dt
                     ipf.mean_sig (nprevl->L, meantme, stdtme, xxs, xxe, yys, yye);
                 }
@@ -1073,7 +1074,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                 float stdtm = stdtms[sp] = stdtme;
                 float meanreti = meanretis[sp] = meanretie;
                 float stdreti = stdretis[sp] = stdretie;
-                
+
                 CurveFactory::complexCurvelocal(ecomp, black / 65535., hlcompr, hlcomprthresh, shcompr, br, cont, lumar,
                                                 hltonecurveloc, shtonecurveloc, tonecurveloc, lightCurveloc, avg,
                                                 sca);
@@ -1125,7 +1126,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                               locccmasblCurve, lcmasblutili, locllmasblCurve, llmasblutili, lochhmasblCurve, lhmasblutili,
                               locccmaslcCurve, lcmaslcutili, locllmaslcCurve, llmaslcutili, lochhmaslcCurve, lhmaslcutili,
                               locccmaslogCurve, lcmaslogutili, locllmaslogCurve, llmaslogutili, lochhmaslogCurve, lhmaslogutili,
-                              
+
                               locccmas_Curve, lcmas_utili, locllmas_Curve, llmas_utili, lochhmas_Curve, lhmas_utili,
                               lochhhmas_Curve, lhhmas_utili,
                               loclmasCurveblwav, lmasutiliblwav,
@@ -1145,13 +1146,13 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                               meantm, stdtm, meanreti, stdreti);
 
 
-                
+
                 if(istm) { //calculate mean and sigma on full image for use by normalize_mean_dt
                     float meanf = 0.f;
                     float stdf = 0.f;
                     ipf.mean_sig (savenormtm.get()->L, meanf, stdf, xxs, xxe, yys, yye);
-                    
-                    //using 2 unused variables  noiselumc and softradiustm  
+
+                    //using 2 unused variables  noiselumc and softradiustm
                     params->locallab.spots.at(sp).noiselumc = (int) meanf;
                     params->locallab.spots.at(sp).softradiustm = stdf ;
                 }
@@ -1160,7 +1161,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                     float meanf = 0.f;
                     float stdf = 0.f;
                     ipf.mean_sig (savenormreti.get()->L, meanf, stdf,xxs, xxe, yys, yye );
-                    //using 2 unused variables  sensihs and sensiv  
+                    //using 2 unused variables  sensihs and sensiv
                     params->locallab.spots.at(sp).sensihs = (int) meanf;
                     params->locallab.spots.at(sp).sensiv = (int) stdf;
                 }
@@ -1207,9 +1208,9 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
             //*************************************************************
             // end locallab
             //*************************************************************
-            
+
         }
-        
+
         if ((todo & M_RGBCURVE) || (todo & M_CROP)) {
             //complexCurve also calculated pre-curves histogram depending on crop
             CurveFactory::complexCurve(params->toneCurve.expcomp, params->toneCurve.black / 65535.0,
@@ -1412,7 +1413,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                 bool proedge = WaveParams.expedge;
                 bool profin = WaveParams.expfinal;
                 bool proton = WaveParams.exptoning;
-                bool pronois = WaveParams.expnoise; 
+                bool pronois = WaveParams.expnoise;
 
                 if(WaveParams.showmask) {
                  //   WaveParams.showmask = false;
@@ -1436,7 +1437,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                     WaveParams.expedge = false;
                     WaveParams.expfinal = false;
                     WaveParams.exptoning = false;
-                    WaveParams.expnoise = false; 
+                    WaveParams.expnoise = false;
                 }
 
                 ipf.ip_wavelet(nprevl, nprevl, kall, WaveParams, wavCLVCurve, wavdenoise, wavdenoiseh, wavblcurve, waOpacityCurveRG, waOpacityCurveSH, waOpacityCurveBY, waOpacityCurveW, waOpacityCurveWL, wavclCurve, scale);
@@ -1449,7 +1450,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                     WaveParams.expfinal = profin;
                     WaveParams.exptoning = proton;
                     WaveParams.expnoise = pronois;
-                    
+
                     if (WaveParams.softrad > 0.f) {
 
                         array2D<float> ble(pW, pH);
@@ -1479,7 +1480,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                                 tmpImage->b(ir, jr) = Z;
                                 ble[ir][jr] = Y / 32768.f;
                             }
-    
+
                         double epsilmax = 0.0001;
                         double epsilmin = 0.00001;
                         double aepsil = (epsilmax - epsilmin) / 100.f;
@@ -1505,11 +1506,11 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                                 Color::XYZ2Lab(X, Y, Z, L, a, b);
                                 nprevl->L[ir][jr] =  L;
                             }
-      
+
                     delete tmpImage;
 
                     }
-                    
+
                 }
 
                 if ((WaveParams.ushamethod == "sharp" || WaveParams.ushamethod == "clari")  && WaveParams.expclari && WaveParams.CLmethod != "all") {
@@ -1518,7 +1519,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
                     float mL0;
                     float mC0;
                     float background = 0.f;
-                    int show = 0; 
+                    int show = 0;
 
 
 
@@ -1560,8 +1561,8 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
 
                     delete unshar;
                     unshar    = NULL;
-                    
-                    
+
+
 /*
                     if (WaveParams.softrad > 0.f) {
                         array2D<float> ble(pW, pH);
@@ -1606,7 +1607,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
 
 
                 }
-               
+
             }
 
             ipf.softLight(nprevl, params->softlight);
@@ -1689,7 +1690,7 @@ void ImProcCoordinator::updatePreviewImage(int todo, bool panningRelatedChange)
               //      acListener->wbCamChanged(params->wb.temperature, params->wb.green);    //real temp and tint
                //     acListener->wbCamChanged(params->wb.temperature, 1.f);    //real temp and tint = 1.
                // }
-                
+
             } else {
                 // CIECAM is disabled, we free up its image buffer to save some space
                 if (ncie) {
@@ -2127,7 +2128,7 @@ bool ImProcCoordinator::getAutoWB(double& temp, double& green, double equal, dou
 // Issue 2500            MyMutex::MyLock lock(minit);  // Also used in crop window
             double rm, gm, bm;
             params->wb.method = "autold";//same result as before muliple Auto WB
-            
+
            // imgsrc->getAutoWBMultipliers(rm, gm, bm);
             double tempitc = 5000.;
             double greenitc = 1.;
@@ -2374,7 +2375,7 @@ void ImProcCoordinator::saveInputICCReference(const Glib::ustring& fname, bool a
         im = tempImage;
     }
 
-    im->setMetadata(MetadataInfo(imgsrc->getFileName()));
+    im->setMetadata(Exiv2Metadata(imgsrc->getFileName(), false));
 
     im->saveTIFF(fname, 16, false, true);
     delete im;
diff --git a/rtengine/metadata.cc b/rtengine/metadata.cc
new file mode 100644
index 000000000..15ab7db44
--- /dev/null
+++ b/rtengine/metadata.cc
@@ -0,0 +1,291 @@
+/* -*- C++ -*-
+ *
+ *  This file is part of RawTherapee.
+ *
+ *  Copyright (c) 2019 Alberto Griggio <alberto.griggio@gmail.com>
+ *
+ *  RawTherapee is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  RawTherapee is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with RawTherapee.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdio.h>
+#include <glib/gstdio.h>
+#include "metadata.h"
+#include "settings.h"
+#include "../rtgui/version.h"
+#include "../rtgui/pathutils.h"
+
+
+namespace rtengine {
+
+extern const Settings *settings;
+
+
+namespace {
+
+Exiv2::Image::AutoPtr open_exiv2(const Glib::ustring& fname)
+{
+#ifdef EXV_UNICODE_PATH
+    glong ws_size = 0;
+    gunichar2* const ws = g_utf8_to_utf16(fname.c_str(), -1, nullptr, &ws_size, nullptr);
+    std::wstring wfname;
+    wfname.reserve(ws_size);
+    for (glong i = 0; i < ws_size; ++i) {
+        wfname.push_back(ws[i]);
+    }
+    g_free(ws);
+    auto image = Exiv2::ImageFactory::open(wfname);
+#else
+    auto image = Exiv2::ImageFactory::open(Glib::filename_from_utf8(fname));
+#endif
+    return image;
+}
+
+} // namespace
+
+
+Exiv2Metadata::Exiv2Metadata():
+    src_(""),
+    merge_xmp_(false),
+    image_(nullptr),
+    exif_(new rtengine::procparams::ExifPairs),
+    iptc_(new rtengine::procparams::IPTCPairs)
+{
+}
+
+
+Exiv2Metadata::Exiv2Metadata(const Glib::ustring &path):
+    src_(""),
+    merge_xmp_(settings->metadata_xmp_sync != Settings::MetadataXmpSync::NONE),
+    image_(nullptr),
+    exif_(new rtengine::procparams::ExifPairs),
+    iptc_(new rtengine::procparams::IPTCPairs)
+{
+}
+
+
+Exiv2Metadata::Exiv2Metadata(const Glib::ustring &path, bool merge_xmp_sidecar):
+    src_(path),
+    merge_xmp_(merge_xmp_sidecar),
+    image_(nullptr),
+    exif_(new rtengine::procparams::ExifPairs),
+    iptc_(new rtengine::procparams::IPTCPairs)
+{
+}
+
+
+void Exiv2Metadata::load() const
+{
+    if (!src_.empty() && !image_.get()) {
+        auto img = open_exiv2(src_);
+        image_.reset(img.release());
+        image_->readMetadata();
+
+        if (merge_xmp_) {
+            do_merge_xmp(image_.get());
+        }
+    }
+}
+
+Exiv2::ExifData& Exiv2Metadata::exifData()
+{
+    return image_.get() ? image_->exifData() : exif_data_;
+}
+
+const Exiv2::ExifData& Exiv2Metadata::exifData() const
+{
+    return const_cast<Exiv2Metadata *>(this)->exifData();
+}
+
+Exiv2::IptcData& Exiv2Metadata::iptcData()
+{
+    return image_.get() ? image_->iptcData() : iptc_data_;
+}
+
+const Exiv2::IptcData& Exiv2Metadata::iptcData() const
+{
+    return const_cast<Exiv2Metadata *>(this)->iptcData();
+}
+
+Exiv2::XmpData& Exiv2Metadata::xmpData()
+{
+    return image_.get() ? image_->xmpData() : xmp_data_;
+}
+
+const Exiv2::XmpData& Exiv2Metadata::xmpData() const
+{
+    return const_cast<Exiv2Metadata *>(this)->xmpData();
+}
+
+const Glib::ustring& Exiv2Metadata::filename() const
+{
+    return src_;
+}
+
+const rtengine::procparams::ExifPairs& Exiv2Metadata::exif() const
+{
+    return *exif_;
+}
+
+const rtengine::procparams::IPTCPairs& Exiv2Metadata::iptc() const
+{
+    return *iptc_;
+}
+
+void Exiv2Metadata::setExif(const rtengine::procparams::ExifPairs &exif)
+{
+    *exif_ = exif;
+}
+
+void Exiv2Metadata::setIptc(const rtengine::procparams::IPTCPairs &iptc)
+{
+    *iptc_ = iptc;
+}
+
+void Exiv2Metadata::do_merge_xmp(Exiv2::Image *dst) const
+{
+    auto xmp = getXmpSidecar(src_);
+    Exiv2::ExifData exif;
+    Exiv2::IptcData iptc;
+    Exiv2::moveXmpToExif(xmp, exif);
+    Exiv2::moveXmpToIptc(xmp, iptc);
+
+    for (auto &datum : exif) {
+        dst->exifData()[datum.key()] = datum;
+    }
+    for (auto &datum : iptc) {
+        dst->iptcData()[datum.key()] = datum;
+    }
+    for (auto &datum : xmp) {
+        dst->xmpData()[datum.key()] = datum;
+    }
+}
+
+
+void Exiv2Metadata::saveToImage(const Glib::ustring &path) const
+{
+    auto dst = open_exiv2(path);
+    dst->readMetadata();
+    if (image_.get()) {
+        dst->setMetadata(*image_);
+        if (merge_xmp_) {
+            do_merge_xmp(dst.get());
+        }
+    } else {
+        dst->setExifData(exif_data_);
+        dst->setIptcData(iptc_data_);
+        dst->setXmpData(xmp_data_);
+    }
+
+    dst->exifData()["Exif.Image.Software"] = "RawTherapee " RTVERSION;
+    import_exif_pairs(dst->exifData());
+    import_iptc_pairs(dst->iptcData());
+    dst->writeMetadata();    
+}
+
+
+void Exiv2Metadata::import_exif_pairs(Exiv2::ExifData &out) const
+{
+    for (auto &p : *exif_) {
+        try {
+            out[p.first] = p.second;
+        } catch (Exiv2::AnyError &exc) {}
+    }
+}
+
+
+void Exiv2Metadata::import_iptc_pairs(Exiv2::IptcData &out) const
+{
+    for (auto &p : *iptc_) {
+        try {
+            auto &v = p.second;
+            if (v.size() >= 1) {
+                out[p.first] = v[0];
+                for (size_t j = 1; j < v.size(); ++j) {
+                    Exiv2::Iptcdatum d(Exiv2::IptcKey(p.first));
+                    d.setValue(v[j]);
+                    out.add(d);
+                }
+            }
+        } catch (Exiv2::AnyError &exc) {}
+    }
+}
+
+
+void Exiv2Metadata::saveToXmp(const Glib::ustring &path) const
+{
+    Exiv2::XmpData xmp;
+    Exiv2::copyExifToXmp(exifData(), xmp);
+    Exiv2::copyIptcToXmp(iptcData(), xmp);
+    for (auto &datum : xmpData()) {
+        xmp[datum.key()] = datum;
+    }
+    Exiv2::ExifData exif;
+    Exiv2::IptcData iptc;
+    import_exif_pairs(exif);
+    import_iptc_pairs(iptc);
+    Exiv2::copyExifToXmp(exif, xmp);
+    Exiv2::copyIptcToXmp(iptc, xmp);
+
+    std::string data;
+    bool err = false;
+    if (Exiv2::XmpParser::encode(data, xmp, Exiv2::XmpParser::omitPacketWrapper|Exiv2::XmpParser::useCompactFormat) != 0) {
+        err = true;
+    } else {
+        FILE *out = g_fopen(path.c_str(), "wb");
+        if (!out || fputs(data.c_str(), out) == EOF) {
+            err = true;
+        }
+        if (out) {
+            fclose(out);
+        }
+    }
+
+    class Error: public Exiv2::AnyError {
+    public:
+        Error(const std::string &msg): msg_(msg) {}
+        const char *what() const throw() { return msg_.c_str(); }
+        int code() const throw() { return 0; }
+
+    private:
+        std::string msg_;
+    };
+    if (err) {
+        throw Error("error saving XMP sidecar " + path);
+    }
+}
+
+
+Glib::ustring Exiv2Metadata::xmpSidecarPath(const Glib::ustring &path)
+{
+    Glib::ustring fn = path;
+    if (settings->xmp_sidecar_style == Settings::XmpSidecarStyle::STD) {
+        fn = removeExtension(fn);
+    }
+    return fn + ".xmp";
+}
+
+
+Exiv2::XmpData Exiv2Metadata::getXmpSidecar(const Glib::ustring &path)
+{
+    Exiv2::XmpData ret;
+    auto fname = xmpSidecarPath(path);
+    if (Glib::file_test(fname, Glib::FILE_TEST_EXISTS)) {
+        auto image = open_exiv2(fname);
+        image->readMetadata();
+        ret = image->xmpData();
+    }
+    return ret;
+}
+
+} // namespace rtengine
diff --git a/rtengine/metadata.h b/rtengine/metadata.h
new file mode 100644
index 000000000..8de384479
--- /dev/null
+++ b/rtengine/metadata.h
@@ -0,0 +1,80 @@
+/* -*- C++ -*-
+ *
+ *  This file is part of RawTherapee.
+ *
+ *  Copyright (c) 2019 Alberto Griggio <alberto.griggio@gmail.com>
+ *
+ *  RawTherapee is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  RawTherapee is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with RawTherapee.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <glibmm.h>
+#include <exiv2/exiv2.hpp>
+#include <memory>
+#include "procparams.h"
+
+namespace rtengine {
+
+class Exiv2Metadata final
+{
+public:
+    Exiv2Metadata();
+    explicit Exiv2Metadata(const Glib::ustring& path);
+    Exiv2Metadata(const Glib::ustring& path, bool merge_xmp_sidecar);
+
+    void load() const;
+    
+    Exiv2::ExifData& exifData();
+    const Exiv2::ExifData& exifData() const;
+    
+    Exiv2::IptcData& iptcData();
+    const Exiv2::IptcData& iptcData() const;
+    
+    Exiv2::XmpData& xmpData();
+    const Exiv2::XmpData& xmpData() const;
+
+    const Glib::ustring& filename() const;
+    const rtengine::procparams::ExifPairs& exif() const;
+    const rtengine::procparams::IPTCPairs& iptc() const;
+    void setExif(const rtengine::procparams::ExifPairs& exif);
+    void setIptc(const rtengine::procparams::IPTCPairs& iptc);
+    
+    void saveToImage(const Glib::ustring& path) const;
+    void saveToXmp(const Glib::ustring& path) const;
+
+    static Glib::ustring xmpSidecarPath(const Glib::ustring& path);
+    static Exiv2::XmpData getXmpSidecar(const Glib::ustring& path);
+   
+private:
+    void do_merge_xmp(Exiv2::Image* dst) const;
+    void import_exif_pairs(Exiv2::ExifData& out) const;
+    void import_iptc_pairs(Exiv2::IptcData& out) const;
+    
+    Glib::ustring src_;
+    bool merge_xmp_;
+    mutable std::shared_ptr<Exiv2::Image> image_;
+    std::unique_ptr<rtengine::procparams::ExifPairs> exif_;
+    std::unique_ptr<rtengine::procparams::IPTCPairs> iptc_;
+    Exiv2::ExifData exif_data_;
+    Exiv2::IptcData iptc_data_;
+    Exiv2::XmpData xmp_data_;
+};
+
+// Glib::ustring get_xmp_sidecar_path(const Glib::ustring &path);
+// Exiv2::Image::AutoPtr open_exiv2(const Glib::ustring &fname,
+//                                  bool merge_xmp_sidecar);
+// Exiv2::XmpData read_exiv2_xmp(const Glib::ustring &fname);
+
+} // namespace rtengine
diff --git a/rtengine/procparams.h b/rtengine/procparams.h
index f72d12f81..4a1eb47e3 100644
--- a/rtengine/procparams.h
+++ b/rtengine/procparams.h
@@ -1773,6 +1773,11 @@ public:
         return pairs.erase(key);
     }
 
+    bool empty() const
+    {
+        return pairs.empty();
+    }
+
     Glib::ustring& operator[](const Glib::ustring& key)
     {
         return pairs[key];
diff --git a/rtengine/settings.h b/rtengine/settings.h
index 0fb4996df..f9ba55257 100644
--- a/rtengine/settings.h
+++ b/rtengine/settings.h
@@ -1,4 +1,5 @@
-/*
+/* -*- C++ -*-
+ *  
  *  This file is part of RawTherapee.
  *
  *  Copyright (c) 2004-2010 Gabor Horvath <hgabor@rawtherapee.com>
@@ -112,6 +113,19 @@ public:
     };
     ThumbnailInspectorMode thumbnail_inspector_mode;
 
+    enum class XmpSidecarStyle {
+        STD, // FILENAME.xmp for FILENAME.ext
+        EXT  // FILENAME.ext.xmp for FILENAME.ext
+    };
+    XmpSidecarStyle xmp_sidecar_style;
+
+    enum class MetadataXmpSync {
+        NONE,
+        READ,
+        READ_WRITE
+    };
+    MetadataXmpSync metadata_xmp_sync;
+
     /** Creates a new instance of Settings.
       * @return a pointer to the new Settings instance. */
     static Settings* create();
diff --git a/rtengine/simpleprocess.cc b/rtengine/simpleprocess.cc
index 6ae805d94..0b6406b62 100644
--- a/rtengine/simpleprocess.cc
+++ b/rtengine/simpleprocess.cc
@@ -37,6 +37,7 @@
 #include "mytime.h"
 #include "guidedfilter.h"
 #include "color.h"
+#include "metadata.h"
 
 #undef THREAD_PRIORITY_NORMAL
 
@@ -945,10 +946,10 @@ private:
 
         if (params.locallab.enabled && params.locallab.spots.size() > 0) {
             ipf.rgb2lab(*baseImg, *labView, params.icm.workingProfile);
-            
+
             MyTime t1, t2;
             t1.set();
-            
+
             const std::unique_ptr<LabImage> reservView(new LabImage(*labView, true));
             const std::unique_ptr<LabImage> lastorigView(new LabImage(*labView, true));
             std::unique_ptr<LabImage> savenormtmView;
@@ -994,7 +995,7 @@ private:
             LocLLmaskCurve locllmas_Curve;
             LocHHmaskCurve lochhmas_Curve;
             LocHHmaskCurve lochhhmas_Curve;
-            
+
             LocwavCurve loclmasCurveblwav;
             LocwavCurve loclmasCurvecolwav;
             LocwavCurve loclmasCurve_wav;
@@ -1073,7 +1074,7 @@ private:
                 const bool lcmaslogutili = locccmaslogCurve.Set(params.locallab.spots.at(sp).CCmaskcurveL);
                 const bool llmaslogutili = locllmaslogCurve.Set(params.locallab.spots.at(sp).LLmaskcurveL);
                 const bool lhmaslogutili = lochhmaslogCurve.Set(params.locallab.spots.at(sp).HHmaskcurveL);
-                
+
                 const bool lcmas_utili = locccmas_Curve.Set(params.locallab.spots.at(sp).CCmask_curve);
                 const bool llmas_utili = locllmas_Curve.Set(params.locallab.spots.at(sp).LLmask_curve);
                 const bool lhmas_utili = lochhmas_Curve.Set(params.locallab.spots.at(sp).HHmask_curve);
@@ -1129,7 +1130,7 @@ private:
                 float stdtme;
                 float meanretie;
                 float stdretie;
-                
+
                 if (params.locallab.spots.at(sp).spotMethod == "exc") {
                     ipf.calc_ref(sp, reservView.get(), reservView.get(), 0, 0, fw, fh, 1, huerefblu, chromarefblu, lumarefblu, huere, chromare, lumare, sobelre, avge, locwavCurveden, locwavdenutili);
                 } else {
@@ -1148,8 +1149,8 @@ private:
                 float Tmax;
 
                 // No Locallab mask is shown in exported picture
-                ipf.Lab_Local(2, sp, shbuffer, labView, labView, reservView.get(), savenormtmView.get(), savenormretiView.get(), lastorigView.get(), 0, 0, fw, fh,  1, locRETgainCurve, locRETtransCurve, 
-                        lllocalcurve, locallutili, 
+                ipf.Lab_Local(2, sp, shbuffer, labView, labView, reservView.get(), savenormtmView.get(), savenormretiView.get(), lastorigView.get(), 0, 0, fw, fh,  1, locRETgainCurve, locRETtransCurve,
+                        lllocalcurve, locallutili,
                         cllocalcurve, localclutili,
                         lclocalcurve, locallcutili,
                         loclhCurve, lochhCurve, locchCurve,
@@ -1164,7 +1165,7 @@ private:
                         lmasklclocalcurve, localmasklcutili,
                         lmaskloglocalcurve, localmasklogutili,
                         lmasklocal_curve, localmask_utili,
-                        
+
                         locccmasCurve, lcmasutili, locllmasCurve, llmasutili, lochhmasCurve, lhmasutili, lochhhmasCurve, lhhmasutili, locccmasexpCurve, lcmasexputili, locllmasexpCurve, llmasexputili, lochhmasexpCurve, lhmasexputili,
                         locccmasSHCurve, lcmasSHutili, locllmasSHCurve, llmasSHutili, lochhmasSHCurve, lhmasSHutili,
                         locccmasvibCurve, lcmasvibutili, locllmasvibCurve, llmasvibutili, lochhmasvibCurve, lhmasvibutili,
@@ -1428,8 +1429,8 @@ private:
             bool proedge = WaveParams.expedge;
             bool profin = WaveParams.expfinal;
             bool proton = WaveParams.exptoning;
-            bool pronois = WaveParams.expnoise; 
-            
+            bool pronois = WaveParams.expnoise;
+
 /*
             if(WaveParams.showmask) {
                 WaveParams.showmask = false;
@@ -1456,7 +1457,7 @@ private:
                 WaveParams.expedge = false;
                 WaveParams.expfinal = false;
                 WaveParams.exptoning = false;
-                WaveParams.expnoise = false; 
+                WaveParams.expnoise = false;
             }
 
             ipf.ip_wavelet(labView, labView, 2, WaveParams, wavCLVCurve, wavdenoise, wavdenoiseh, wavblcurve, waOpacityCurveRG, waOpacityCurveSH, waOpacityCurveBY, waOpacityCurveW,  waOpacityCurveWL, wavclCurve, 1);
@@ -1468,7 +1469,7 @@ private:
                 WaveParams.expfinal = profin;
                 WaveParams.exptoning = proton;
                 WaveParams.expnoise = pronois;
-                
+
                 if (WaveParams.softrad > 0.f) {
                     array2D<float> ble(fw, fh);
                     array2D<float> guid(fw, fh);
@@ -1523,7 +1524,7 @@ private:
                         }
                 delete tmpImage;
                 }
-                
+
             }
 
             if ((WaveParams.ushamethod == "sharp" || WaveParams.ushamethod == "clari") && WaveParams.expclari && WaveParams.CLmethod != "all") {
@@ -1730,7 +1731,7 @@ private:
             readyImg = tempImage;
         }
 
-        MetadataInfo info(imgsrc->getFileName());
+        Exiv2Metadata info(imgsrc->getFileName());
         switch (params.metadata.mode) {
         case MetaDataParams::TUNNEL:
             readyImg->setMetadata(std::move(info));
diff --git a/rtgui/exifpanel.cc b/rtgui/exifpanel.cc
index f452c2491..7438240e9 100644
--- a/rtgui/exifpanel.cc
+++ b/rtgui/exifpanel.cc
@@ -25,6 +25,7 @@
 #include "options.h"
 
 #include "../rtengine/imagedata.h"
+#include "../rtengine/metadata.h"
 #include "../rtengine/procparams.h"
 
 using namespace rtengine;
@@ -225,9 +226,9 @@ void ExifPanel::refreshTags()
     }
 
     try {
-        auto img = open_exiv2(fn);
-        img->readMetadata();
-        auto& exif = img->exifData();
+        rtengine::Exiv2Metadata meta(fn);
+        meta.load();
+        auto& exif = meta.exifData();
 
         for (const auto& p : *changeList) {
             try {
diff --git a/rtgui/iptcpanel.cc b/rtgui/iptcpanel.cc
index 0f8471b92..724b54aa1 100644
--- a/rtgui/iptcpanel.cc
+++ b/rtgui/iptcpanel.cc
@@ -24,6 +24,7 @@
 #include "rtimage.h"
 
 #include "../rtengine/imagedata.h"
+#include "../rtengine/metadata.h"
 #include "../rtengine/procparams.h"
 
 using namespace rtengine;
@@ -493,9 +494,9 @@ void IPTCPanel::setImageData (const FramesMetaData* id)
     embeddedData->clear();
     if (id) {
         try {
-            auto img = open_exiv2(id->getFileName());
-            img->readMetadata();
-            auto& iptc = img->iptcData();
+            rtengine::Exiv2Metadata meta(id->getFileName());
+            meta.load();
+            auto& iptc = meta.iptcData();
             for (const auto& tag : iptc) {
                 if (iptc_keys.find(tag.key()) != iptc_keys.end()) {
                     (*embeddedData)[tag.key()].push_back(tag.toString());
diff --git a/rtgui/options.cc b/rtgui/options.cc
index ce03db434..cf2cbaad3 100644
--- a/rtgui/options.cc
+++ b/rtgui/options.cc
@@ -626,7 +626,7 @@ void Options::setDefaults()
     rtSettings.edghi = 3.0;//1.1 and 5.
     rtSettings.edglo = 0.5;//0.1 and 0.95
     rtSettings.limrad = 20.;//1 and 60
-    
+
 
     rtSettings.protectred = 60;
     rtSettings.protectredh = 0.3;
@@ -682,6 +682,9 @@ void Options::setDefaults()
     cropAutoFit = false;
 
     rtSettings.thumbnail_inspector_mode = rtengine::Settings::ThumbnailInspectorMode::JPEG;
+
+    rtSettings.xmp_sidecar_style = rtengine::Settings::XmpSidecarStyle::STD;
+    rtSettings.metadata_xmp_sync = rtengine::Settings::MetadataXmpSync::NONE;
 }
 
 Options* Options::copyFrom(Options* other)
@@ -1488,11 +1491,11 @@ void Options::readFromFile(Glib::ustring fname)
                 if (keyFile.has_key("GUI", "CurveBBoxPosition")) {
                     curvebboxpos = keyFile.get_integer("GUI", "CurveBBoxPosition");
                 }
-                
+
                 if (keyFile.has_key("GUI", "Complexity")) {
                     complexity = keyFile.get_integer("GUI", "Complexity");
                 }
-                
+
                 if (keyFile.has_key("GUI", "InspectorWindow")) {
                     inspectorWindow = keyFile.get_boolean("GUI", "InspectorWindow");
                 }
@@ -1755,8 +1758,8 @@ void Options::readFromFile(Glib::ustring fname)
                 }
 
             }
-            
-            
+
+
             if (keyFile.has_group("ICC Profile Creator")) {
                 if (keyFile.has_key("ICC Profile Creator", "PimariesPreset")) {
                     ICCPC_primariesPreset = keyFile.get_string("ICC Profile Creator", "PimariesPreset");
@@ -2030,6 +2033,27 @@ void Options::readFromFile(Glib::ustring fname)
                 }
             }
 
+            if (keyFile.has_group("Metadata")) {
+                if (keyFile.has_key("Metadata", "XMPSidecarStyle")) {
+                    std::string val = keyFile.get_string("Metadata", "XMPSidecarStyle");
+                    if (val == "ext") {
+                        rtSettings.xmp_sidecar_style = rtengine::Settings::XmpSidecarStyle::EXT;
+                    } else {
+                        rtSettings.xmp_sidecar_style = rtengine::Settings::XmpSidecarStyle::STD;
+                    }
+                }
+                if (keyFile.has_key("Metadata", "XMPSynchronization")) {
+                    std::string val = keyFile.get_string("Metadata", "XMPSynchronization");
+                    if (val == "read") {
+                        rtSettings.metadata_xmp_sync = rtengine::Settings::MetadataXmpSync::READ;
+                    } else if (val == "readwrite") {
+                        rtSettings.metadata_xmp_sync = rtengine::Settings::MetadataXmpSync::READ_WRITE;
+                    } else {
+                        rtSettings.metadata_xmp_sync = rtengine::Settings::MetadataXmpSync::NONE;
+                    }
+                }
+            }
+
 // --------------------------------------------------------------------------------------------------------
 
             filterOutParsedExtensions();
@@ -2448,6 +2472,25 @@ void Options::saveToFile(Glib::ustring fname)
 
         keyFile.set_string("Lensfun", "DBDirectory", rtSettings.lensfunDbDirectory);
 
+        switch (rtSettings.xmp_sidecar_style) {
+        case rtengine::Settings::XmpSidecarStyle::EXT:
+            keyFile.set_string("Metadata", "XMPSidecarStyle", "ext");
+            break;
+        default:
+            keyFile.set_string("Metadata", "XMPSidecarStyle", "std");
+        }
+
+        switch (rtSettings.metadata_xmp_sync) {
+        case rtengine::Settings::MetadataXmpSync::READ:
+            keyFile.set_string("Metadata", "XMPSynchronization", "read");
+            break;
+        case rtengine::Settings::MetadataXmpSync::READ_WRITE:
+            keyFile.set_string("Metadata", "XMPSynchronization", "readwrite");
+            break;
+        default:
+            keyFile.set_string("Metadata", "XMPSynchronization", "none");
+        }
+
         keyData = keyFile.to_data();
 
     } catch (Glib::KeyFileError &e) {
diff --git a/rtgui/preferences.cc b/rtgui/preferences.cc
index 9d9603297..62c243802 100644
--- a/rtgui/preferences.cc
+++ b/rtgui/preferences.cc
@@ -527,7 +527,7 @@ Gtk::Widget* Preferences::getImageProcessingPanel ()
     iprofiles->set_size_request(50, -1);
     setExpandAlignProperties(iprofiles, true, false, Gtk::ALIGN_FILL, Gtk::ALIGN_FILL);
     ipconn = iprofiles->signal_changed().connect(sigc::mem_fun(*this, &Preferences::forImageComboChanged));
-    
+
     Gtk::Grid* defpt = Gtk::manage(new Gtk::Grid());
     defpt->set_row_spacing(2);
     defpt->attach(*drlab, 0, 0, 1, 1);
@@ -535,7 +535,7 @@ Gtk::Widget* Preferences::getImageProcessingPanel ()
     defpt->attach(*drimg, 0, 1, 1, 1);
     defpt->attach(*iprofiles, 1, 1, 1, 1);
     vbpp->pack_start(*defpt, Gtk::PACK_SHRINK, 4);
-    
+
     useBundledProfiles = Gtk::manage(new Gtk::CheckButton(M("PREFERENCES_USEBUNDLEDPROFILES")));
     bpconn = useBundledProfiles->signal_clicked().connect(sigc::mem_fun(*this, &Preferences::bundledProfilesChanged));
     vbpp->pack_start(*useBundledProfiles, Gtk::PACK_SHRINK, 4);
@@ -581,9 +581,36 @@ Gtk::Widget* Preferences::getImageProcessingPanel ()
     fdp->add(*vbdp);
     vbImageProcessing->pack_start (*fdp, Gtk::PACK_SHRINK, 4);
 
-//    Gtk::Frame* fdf = Gtk::manage (new Gtk::Frame (M ("PREFERENCES_DARKFRAME")) );
-//    Gtk::Box* hb42 = Gtk::manage (new Gtk::Box ());
-//    darkFrameDir = Gtk::manage (new Gtk::FileChooserButton (M ("PREFERENCES_DIRDARKFRAMES"), Gtk::FILE_CHOOSER_ACTION_SELECT_FOLDER));
+    // Metadata
+    Gtk::Frame *mf = Gtk::manage(new Gtk::Frame(M("PREFERENCES_METADATA")));
+    Gtk::Grid *mtbl = Gtk::manage(new Gtk::Grid());
+    setExpandAlignProperties(mtbl, true, false, Gtk::ALIGN_FILL, Gtk::ALIGN_CENTER);
+
+    metadataSyncCombo = Gtk::manage(new Gtk::ComboBoxText());
+    metadataSyncCombo->set_active(0);
+    metadataSyncCombo->append(M("PREFERENCES_METADATA_SYNC_NONE"));
+    metadataSyncCombo->append(M("PREFERENCES_METADATA_SYNC_READ"));
+    metadataSyncCombo->append(M("PREFERENCES_METADATA_SYNC_READWRITE"));
+    Gtk::Label *mlbl = Gtk::manage(new Gtk::Label(M("PREFERENCES_METADATA_SYNC") + ": "));
+    mtbl->attach(*mlbl, 0, 0, 1, 1);
+    mtbl->attach_next_to(*metadataSyncCombo, *mlbl, Gtk::POS_RIGHT, 1, 1);
+    setExpandAlignProperties(mlbl, false, false, Gtk::ALIGN_START, Gtk::ALIGN_CENTER);
+    setExpandAlignProperties(metadataSyncCombo, true, false, Gtk::ALIGN_FILL, Gtk::ALIGN_CENTER);
+
+    xmpSidecarCombo = Gtk::manage(new Gtk::ComboBoxText());
+    xmpSidecarCombo->set_active(0);
+    xmpSidecarCombo->append(M("PREFERENCES_XMP_SIDECAR_MODE_STD"));
+    xmpSidecarCombo->append(M("PREFERENCES_XMP_SIDECAR_MODE_EXT"));
+
+    mlbl = Gtk::manage(new Gtk::Label(M("PREFERENCES_XMP_SIDECAR_MODE") + ": "));
+    mtbl->attach(*mlbl, 0, 2, 1, 1);
+    mtbl->attach_next_to(*xmpSidecarCombo, *mlbl, Gtk::POS_RIGHT, 1, 1);
+    setExpandAlignProperties(mlbl, false, false, Gtk::ALIGN_START, Gtk::ALIGN_CENTER);
+    setExpandAlignProperties(xmpSidecarCombo, true, false, Gtk::ALIGN_FILL, Gtk::ALIGN_CENTER);
+
+    mf->add(*mtbl);
+    vbImageProcessing->pack_start(*mf, Gtk::PACK_SHRINK, 4);
+
     // Directories
     Gtk::Frame* cdf = Gtk::manage(new Gtk::Frame(M("PREFERENCES_DIRECTORIES")));
     Gtk::Grid* dirgrid = Gtk::manage(new Gtk::Grid());
@@ -1104,7 +1131,7 @@ Gtk::Widget* Preferences::getGeneralPanel()
     setExpandAlignProperties(pseudoHiDPI, false, false, Gtk::ALIGN_START, Gtk::ALIGN_BASELINE);
 
     Gtk::Separator *vSep = Gtk::manage(new Gtk::Separator(Gtk::ORIENTATION_VERTICAL));
-    
+
 
     appearanceGrid->attach(*themeLbl,           0, 0, 1, 1);
     appearanceGrid->attach(*themeCBT,           1, 0, 1, 1);
@@ -1870,6 +1897,9 @@ void Preferences::storePreferences()
 
     moptions.cropGuides = Options::CropGuidesMode(cropGuidesCombo->get_active_row_number());
     moptions.cropAutoFit = cropAutoFitCB->get_active();
+
+    moptions.rtSettings.metadata_xmp_sync = rtengine::Settings::MetadataXmpSync(metadataSyncCombo->get_active_row_number());
+    moptions.rtSettings.xmp_sidecar_style = rtengine::Settings::XmpSidecarStyle(xmpSidecarCombo->get_active_row_number());
 }
 
 void Preferences::fillPreferences()
@@ -2053,7 +2083,7 @@ void Preferences::fillPreferences()
     }
 
     curveBBoxPosC->set_active(moptions.curvebboxpos);
-    complexitylocal->set_active(moptions.complexity); 
+    complexitylocal->set_active(moptions.complexity);
     inspectorWindowCB->set_active(moptions.inspectorWindow);
     zoomOnScrollCB->set_active(moptions.zoomOnScroll);
 
@@ -2120,6 +2150,9 @@ void Preferences::fillPreferences()
     txtSndLngEditProcDone->set_text(moptions.sndLngEditProcDone);
     spbSndLngEditProcDoneSecs->set_value(moptions.sndLngEditProcDoneSecs);
 #endif
+
+    metadataSyncCombo->set_active(int(moptions.rtSettings.metadata_xmp_sync));
+    xmpSidecarCombo->set_active(int(moptions.rtSettings.xmp_sidecar_style));
 }
 
 /*
diff --git a/rtgui/preferences.h b/rtgui/preferences.h
index df4e3327a..86e81424d 100644
--- a/rtgui/preferences.h
+++ b/rtgui/preferences.h
@@ -223,6 +223,9 @@ class Preferences final :
     Gtk::ComboBoxText *cropGuidesCombo;
     Gtk::CheckButton *cropAutoFitCB;
 
+    Gtk::ComboBoxText *metadataSyncCombo;
+    Gtk::ComboBoxText *xmpSidecarCombo;
+
     Glib::ustring storedValueRaw;
     Glib::ustring storedValueImg;
 
diff --git a/rtgui/thumbnail.cc b/rtgui/thumbnail.cc
index e50d7ac77..31ca8bc1f 100644
--- a/rtgui/thumbnail.cc
+++ b/rtgui/thumbnail.cc
@@ -33,6 +33,7 @@
 #include <glib/gstdio.h>
 
 #include "../rtengine/dynamicprofile.h"
+#include "../rtengine/metadata.h"
 #include "../rtengine/profilestore.h"
 #include "../rtengine/settings.h"
 #include "guiutils.h"
@@ -1026,6 +1027,10 @@ void Thumbnail::updateCache (bool updatePParams, bool updateCacheImageData)
     if (updateCacheImageData) {
         cfs.save (getCacheFileName ("data", ".txt"));
     }
+
+    if (updatePParams && pparamsValid) {
+        saveMetadata();
+    }
 }
 
 Thumbnail::~Thumbnail ()
@@ -1204,6 +1209,33 @@ void Thumbnail::getCamWB(double& temp, double& green) const
     }
 }
 
+void Thumbnail::saveMetadata()
+{
+    if (options.rtSettings.metadata_xmp_sync != rtengine::Settings::MetadataXmpSync::READ_WRITE) {
+        return;
+    }
+
+    if (pparams->exif.empty() && pparams->iptc.empty()) {
+        return;
+    }
+
+    auto fn = rtengine::Exiv2Metadata::xmpSidecarPath(fname);
+    try {
+        auto xmp = rtengine::Exiv2Metadata::getXmpSidecar(fname);
+        rtengine::Exiv2Metadata meta;
+        meta.xmpData() = std::move(xmp);
+        meta.setExif(pparams->exif);
+        meta.setIptc(pparams->iptc);
+        meta.saveToXmp(fn);
+        if (options.rtSettings.verbose) {
+            std::cout << "saved edited metadata for " << fname << " to "
+                      << fn << std::endl;
+        }
+    } catch (Exiv2::AnyError &exc) {
+        std::cerr << "ERROR saving metadata for " << fname << " to " << fn
+                  << ": " << exc.what() << std::endl;
+    }
+}
 void Thumbnail::getSpotWB(int x, int y, int rect, double& temp, double& green)
 {
     if (tpp) {
diff --git a/rtgui/thumbnail.h b/rtgui/thumbnail.h
index 93d1deb93..85701142d 100644
--- a/rtgui/thumbnail.h
+++ b/rtgui/thumbnail.h
@@ -88,6 +88,8 @@ class Thumbnail
 
     Glib::ustring    getCacheFileName (const Glib::ustring& subdir, const Glib::ustring& fext) const;
 
+    void saveMetadata();
+
 public:
     Thumbnail (CacheManager* cm, const Glib::ustring& fname, CacheImageData* cf);
     Thumbnail (CacheManager* cm, const Glib::ustring& fname, const std::string& md5);