diff --git a/src/MaRaCluster.cpp b/src/MaRaCluster.cpp
index f2457df..8f05bba 100644
--- a/src/MaRaCluster.cpp
+++ b/src/MaRaCluster.cpp
@@ -20,9 +20,9 @@ namespace maracluster {
 
 MaRaCluster::MaRaCluster() :
     mode_(NONE), call_(""), percOutFN_(""), fnPrefix_("MaRaCluster"), 
-    peakCountFN_(""), datFNFile_(""), scanInfoFN_(""), pvaluesFN_(""), 
-    clusterFileFN_(""), pvalVecInFileFN_(""), pvalueVectorsBaseFN_(""), 
-    overlapBatchFileFN_(""), overlapBatchIdx_(0u), 
+    peakCountFN_(""), datFNFile_(""), scanInfoFN_(""), addSpecIds_(false),
+    pvaluesFN_(""), clusterFileFN_(""), pvalVecInFileFN_(""), 
+    pvalueVectorsBaseFN_(""), overlapBatchFileFN_(""), overlapBatchIdx_(0u), 
     spectrumBatchFileFN_(""), spectrumInFN_(""), spectrumOutFN_(""),
     spectrumLibraryFN_(""), matrixFN_(""), resultTreeFN_(""),
     skipFilterAndSort_(false), writeAll_(false), precursorTolerance_(20),
@@ -106,6 +106,11 @@ bool MaRaCluster::parseOptions(int argc, char **argv) {
       "dat-folder",
       "Writable folder for converted .dat binary files. Can be used to re-use already converted spectrum files (default: ./maracluster_output/dat_files).",
       "path");
+  cmd.defineOption("I",
+      "addSpecIds",
+      "Add column with spectrum id/title to clustering file output.",
+      "",
+      TRUE_IF_SET);
   cmd.defineOption("a",
       "prefix",
       "Output files will be prefixed as e.g. <prefix>.clusters_p10.tsv (default: 'MaRaCluster')",
@@ -221,7 +226,10 @@ bool MaRaCluster::parseOptions(int argc, char **argv) {
   
   // file input for maracluster batch and index (also for some other methods)
   if (cmd.optionSet("batch")) spectrumBatchFileFN_ = cmd.options["batch"];
-  if (cmd.optionSet("output-folder")) outputFolder_ = cmd.options["output-folder"];
+  if (cmd.optionSet("output-folder")) {
+    outputFolder_ = cmd.options["output-folder"];
+    datFolder_ = outputFolder_ + "/dat_files";
+  }
   if (cmd.optionSet("dat-folder")) datFolder_ = cmd.options["dat-folder"];
   if (cmd.optionSet("prefix")) fnPrefix_ = cmd.options["prefix"];
   
@@ -229,6 +237,7 @@ bool MaRaCluster::parseOptions(int argc, char **argv) {
   if (cmd.optionSet("datFNfile")) datFNFile_ = cmd.options["datFNfile"];
   if (cmd.optionSet("peakCountsFN")) peakCountFN_ = cmd.options["peakCountsFN"];
   if (cmd.optionSet("scanInfoFN")) scanInfoFN_ = cmd.options["scanInfoFN"];
+  if (cmd.optionSet("addSpecIds")) addSpecIds_ = true;
   
   // file input options for maracluster pvalue
   if (cmd.optionSet("specIn")) spectrumInFN_ = cmd.options["specIn"];
@@ -314,7 +323,7 @@ int MaRaCluster::createIndex() {
   fileList.initFromFile(spectrumBatchFileFN_);
   
   if (!Globals::fileExists(datFNFile_) || !Globals::fileExists(scanInfoFN_)) {    
-    SpectrumFiles spectrumFiles(outputFolder_, datFolder_, chargeUncertainty_);
+    SpectrumFiles spectrumFiles(outputFolder_, datFolder_, chargeUncertainty_, addSpecIds_);
     spectrumFiles.convertToDat(fileList);
     spectrumFiles.splitByPrecursorMz(fileList, datFNFile_, peakCountFN_, 
         scanInfoFN_, precursorTolerance_, precursorToleranceDa_);
diff --git a/src/MaRaCluster.h b/src/MaRaCluster.h
index f9fce77..3e5e5ec 100644
--- a/src/MaRaCluster.h
+++ b/src/MaRaCluster.h
@@ -104,6 +104,7 @@ class MaRaCluster {
   std::string peakCountFN_;
   std::string datFNFile_;
   std::string scanInfoFN_;
+  bool addSpecIds_;
   std::string pvaluesFN_;
   std::string clusterFileFN_;
   std::string pvalVecInFileFN_;
diff --git a/src/ScanId.cpp b/src/ScanId.cpp
index ef22186..c608470 100644
--- a/src/ScanId.cpp
+++ b/src/ScanId.cpp
@@ -33,4 +33,9 @@ std::size_t hash_value(ScanId const& si) {
   return hasher((si.fileIdx+1) * 1000000 + si.scannr);
 }
 
+std::ostream& operator<<(std::ostream& stream, const ScanIdExtended& si) {
+  stream << si.scanId.fileIdx << " " << si.scanId.scannr << " " << si.title;
+  return stream;
+}
+
 } /* namespace maracluster */
diff --git a/src/ScanId.h b/src/ScanId.h
index 9fe0fa7..dde21d1 100644
--- a/src/ScanId.h
+++ b/src/ScanId.h
@@ -47,6 +47,13 @@ struct ScanId {
 std::ostream& operator<<(std::ostream& stream, const ScanId& si);
 std::size_t hash_value(ScanId const& si);
 
+struct ScanIdExtended {
+  ScanId scanId;
+  std::string title;
+};
+
+std::ostream& operator<<(std::ostream& stream, const ScanIdExtended& si);
+
 } /* namespace maracluster */
 
 #endif /* MARACLUSTER_SCANID_H_ */
diff --git a/src/Spectra.cpp b/src/Spectra.cpp
index bf09f06..08c81cc 100644
--- a/src/Spectra.cpp
+++ b/src/Spectra.cpp
@@ -36,7 +36,8 @@ void Spectra::convertToBatchSpectra(const std::string& spectrumFN,
   SpectrumFiles specFiles;
   std::vector<Spectrum> localSpectra;
   std::vector<ScanInfo> localScanInfos;
-  specFiles.getBatchSpectra(spectrumFN, fileList, localSpectra, localScanInfos);
+  std::vector<ScanIdExtended> localScanTitles;
+  specFiles.getBatchSpectra(spectrumFN, fileList, localSpectra, localScanInfos, localScanTitles);
   
 #pragma omp critical(append_spectra)
   {
diff --git a/src/SpectrumFiles.cpp b/src/SpectrumFiles.cpp
index e3dfb2e..1e1da4c 100644
--- a/src/SpectrumFiles.cpp
+++ b/src/SpectrumFiles.cpp
@@ -175,7 +175,8 @@ void SpectrumFiles::writeSplittedPrecursorMzFiles(
 void SpectrumFiles::getBatchSpectra(
     const std::string& spectrumFN, SpectrumFileList& fileList,
     std::vector<Spectrum>& localSpectra, 
-    std::vector<ScanInfo>& scanInfos) {
+    std::vector<ScanInfo>& scanInfos,
+    std::vector<ScanIdExtended>& scanTitles) {
   if ( !boost::filesystem::exists( spectrumFN ) ) {
     std::cerr << "Ignoring missing file " << spectrumFN << std::endl;
     return;
@@ -199,6 +200,13 @@ void SpectrumFiles::getBatchSpectra(
     ScanInfo scanInfo;
     scanInfo.scanId = fileList.getScanId(spectrumFN, scannr);
     
+    if (addSpecIds_) {
+      ScanIdExtended scanTitle;
+      scanTitle.scanId = scanInfo.scanId;
+      scanTitle.title = SpectrumHandler::getScanTitle(s);
+      scanTitles.push_back(scanTitle);
+    }
+    
     std::vector<MassChargeCandidate> mccs;
     getMassChargeCandidates(s, mccs, scanInfo.scanId);
     
@@ -293,17 +301,22 @@ void SpectrumFiles::convertAndWriteDatFiles(
     const std::string& spectrumFN) {
   std::string datFile = SpectrumFiles::getOutputFile(spectrumFN, datFolder_, ".dat");
   std::string scanInfoFile = SpectrumFiles::getOutputFile(spectrumFN, datFolder_, ".scan_info.dat");
+  std::string scanTitleFile = SpectrumFiles::getOutputFile(spectrumFN, datFolder_, ".scan_titles.txt");
   if (boost::filesystem::exists(datFile) && boost::filesystem::exists(scanInfoFile)) {
     return;
   }
   
   std::vector<Spectrum> localSpectra;
   std::vector<ScanInfo> scanInfos;
-  getBatchSpectra(spectrumFN, fileList, localSpectra, scanInfos);
+  std::vector<ScanIdExtended> scanTitles;
+  getBatchSpectra(spectrumFN, fileList, localSpectra, scanInfos, scanTitles);
   
   bool append = false;
   BinaryInterface::write<Spectrum>(localSpectra, datFile, append);
   BinaryInterface::write<ScanInfo>(scanInfos, scanInfoFile, append);
+  if (addSpecIds_) {
+    writeScanTitlesToFile(scanTitles, scanTitleFile);
+  }
 }
 
 void SpectrumFiles::readDatFNsFromFile(const std::string& datFNFile,
@@ -331,6 +344,18 @@ void SpectrumFiles::writeDatFNsToFile(std::vector<std::string>& datFNs,
   }
 }
 
+void SpectrumFiles::writeScanTitlesToFile(std::vector<ScanIdExtended>& scanTitles,
+    const std::string& scanTitlesFile) {
+  std::ofstream outfile(scanTitlesFile.c_str(), std::ios_base::out);
+  if (outfile.is_open()) {
+    BOOST_FOREACH (const ScanIdExtended& scanTitle, scanTitles) {
+      outfile << scanTitle << "\n";
+    }
+  } else {
+    std::cerr << "Could not write scan titles to file" << std::endl;
+  }
+}
+
 void SpectrumFiles::writePrecMzs(const std::vector<double>& precMzs) {
   BOOST_FOREACH (const double precMz, precMzs) {
     std::cout << precMz << std::endl;
diff --git a/src/SpectrumFiles.h b/src/SpectrumFiles.h
index 7b6671b..aa41b31 100644
--- a/src/SpectrumFiles.h
+++ b/src/SpectrumFiles.h
@@ -65,18 +65,21 @@ struct ScanInfo {
 
 class SpectrumFiles {
  public:
-  SpectrumFiles() : outputFolder_(""), chargeUncertainty_(0) {}
+  SpectrumFiles() : outputFolder_(""), chargeUncertainty_(0), datFolder_(""), addSpecIds_(false) {}
   SpectrumFiles(const std::string& precMzFileFolder,
                 const std::string& datFolder) : 
       outputFolder_(precMzFileFolder), 
       datFolder_(datFolder), 
-      chargeUncertainty_(0) {}
+      chargeUncertainty_(0),
+      addSpecIds_(false) {}
   SpectrumFiles(const std::string& precMzFileFolder, 
                 const std::string& datFolder,
-                const int chargeUncertainty) : 
+                const int chargeUncertainty,
+                const bool addSpecIds) : 
       outputFolder_(precMzFileFolder),
       datFolder_(datFolder),
-      chargeUncertainty_(chargeUncertainty) {}
+      chargeUncertainty_(chargeUncertainty),
+      addSpecIds_(addSpecIds) {}
   
   void convertToDat(SpectrumFileList& fileList);
   void splitByPrecursorMz(SpectrumFileList& fileList,
@@ -93,17 +96,19 @@ class SpectrumFiles {
   
   void getBatchSpectra(const std::string& spectrumFN, 
     SpectrumFileList& fileList, std::vector<Spectrum>& localSpectra,
-    std::vector<ScanInfo>& localScanInfos);
+    std::vector<ScanInfo>& localScanInfos,
+    std::vector<ScanIdExtended>& scanTitles);
   
   void getDatFNs(std::vector<double>& limits, 
     std::vector<std::string>& datFNs);
-    
   static void writeDatFNsToFile(std::vector<std::string>& datFNs,
     const std::string& datFNFile);
-  
   static void readDatFNsFromFile(const std::string& datFNFile,
     std::vector<std::string>& datFNs);
   
+  static void writeScanTitlesToFile(std::vector<ScanIdExtended>& scanTitles,
+    const std::string& scanTitlesFile);
+    
   static void readPrecMzLimits(const std::string& scanInfoFN,
     std::map<ScanId, std::pair<float, float> >& precMzLimits);
   
@@ -113,6 +118,7 @@ class SpectrumFiles {
   std::string outputFolder_;
   std::string datFolder_;
   int chargeUncertainty_;
+  bool addSpecIds_;
   
   virtual void getMassChargeCandidates(pwiz::msdata::SpectrumPtr s, 
     std::vector<MassChargeCandidate>& mccs, ScanId scanId);
diff --git a/src/SpectrumHandler.cpp b/src/SpectrumHandler.cpp
index 1990544..f581d52 100644
--- a/src/SpectrumHandler.cpp
+++ b/src/SpectrumHandler.cpp
@@ -24,7 +24,8 @@ unsigned int SpectrumHandler::getScannr(pwiz::msdata::SpectrumPtr s) {
     std::string mgfScansField = s->cvParam(pwiz::cv::MS_peak_list_scans).valueAs<std::string>();
     return atoi(mgfScansField.c_str());
   }
-  std::stringstream ss(s->id);
+  std::string scanTitle = SpectrumHandler::getScanTitle(s);
+  std::stringstream ss(scanTitle);
   while (ss.good()) {
     std::string tmp;
     ss >> tmp;
@@ -56,6 +57,15 @@ void SpectrumHandler::setScannr(pwiz::msdata::SpectrumPtr s, const ScanId& scanI
   setScannr(s, hash_value(scanId));
 }
 
+std::string SpectrumHandler::getScanTitle(pwiz::msdata::SpectrumPtr s) {
+  // special check for the TITLE field in mgf files
+  if (s->hasCVParam(pwiz::msdata::MS_spectrum_title)) {
+    std::string mgfScanTitle = s->cvParam(pwiz::msdata::MS_spectrum_title).valueAs<std::string>();
+    return mgfScanTitle;
+  }
+  return s->id;
+}
+
 double SpectrumHandler::interpolateIntensity(MZIntensityPair p1, MZIntensityPair p2, double mz) {
   return ( (p2.intensity - p1.intensity) / (p2.mz - p1.mz) * (mz - p1.mz) + p1.intensity );
 }
diff --git a/src/SpectrumHandler.h b/src/SpectrumHandler.h
index 5532cf9..48ba19a 100644
--- a/src/SpectrumHandler.h
+++ b/src/SpectrumHandler.h
@@ -70,6 +70,8 @@ class SpectrumHandler {
   static void setScannr(pwiz::msdata::SpectrumPtr s, unsigned int scanNr);
   static void setScannr(pwiz::msdata::SpectrumPtr s, const ScanId& scanId);
   
+  static std::string getScanTitle(pwiz::msdata::SpectrumPtr s);
+  
   static double interpolateIntensity(MZIntensityPair p1, MZIntensityPair p2, double mz);
   static void scaleIntensities(std::vector<MZIntensityPair>& mziPairs, double scaling);