diff --git a/Trigger/TrigConfiguration/TrigConfHLTData/Root/HLTFrame.cxx b/Trigger/TrigConfiguration/TrigConfHLTData/Root/HLTFrame.cxx
index 9eade534ec608d01ec50b1b97ba43d85b50253ef..53587869bda2f263babd16178780f3f54d3d53b1 100644
--- a/Trigger/TrigConfiguration/TrigConfHLTData/Root/HLTFrame.cxx
+++ b/Trigger/TrigConfiguration/TrigConfHLTData/Root/HLTFrame.cxx
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
 
 #include "TrigConfHLTData/HLTFrame.h"
@@ -35,9 +35,9 @@ HLTFrame::~HLTFrame()
 
 void
 HLTFrame::clear() {
-   theHLTChainList().clear();
-   theHLTSequenceList().clear();
-   thePrescaleSetCollection().clear();
+   m_HLTChainList.clear();
+   m_HLTSequenceList.clear();
+   m_hltPrescaleSets.clear();
 
    setId(0);
    setName("");
@@ -147,25 +147,3 @@ TrigConf::operator<<(std::ostream & o, const TrigConf::HLTFrame & f) {
      << f.getHLTSequenceList();
    return o;
 }
-
-
-// for python
-vector<TrigConf::HLTChain*>
-HLTFrame::chainsV() const {
-   vector<HLTChain*> ch(chains().size());
-   copy(chains().begin(), chains().end(), ch.begin());
-   return ch;
-}
-
-vector<TrigConf::HLTSequence*>
-HLTFrame::sequencesV() const {
-   vector<HLTSequence*> seq(sequences().size());
-   copy(sequences().begin(), sequences().end(), seq.begin());
-   return seq;
-}
-
-string HLTFrame::__str__() const {
-   stringstream s;
-   s << *this;
-   return s.str();
-}
diff --git a/Trigger/TrigConfiguration/TrigConfHLTData/Root/HLTUtils.cxx b/Trigger/TrigConfiguration/TrigConfHLTData/Root/HLTUtils.cxx
index 9c1e43ed8889906862bbcaf0dca7c05b4a64b357..d29913281613a0ec853d5afeb5768181e1ef2d04 100644
--- a/Trigger/TrigConfiguration/TrigConfHLTData/Root/HLTUtils.cxx
+++ b/Trigger/TrigConfiguration/TrigConfHLTData/Root/HLTUtils.cxx
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2020 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
 
 #include <iostream>
@@ -69,7 +69,7 @@ namespace TrigConf {
                              const std::set<std::string>* veto = 0 )
    {
       if ( veto && veto->find(tename) != veto->end() ) return;
-      const TrigConf::HLTSequence* seq = sequenceList.getSequence(tename);
+      TrigConf::HLTSequence* seq = sequenceList.getSequence(tename);
       if ( seq==0 ) return;
 
       if(level==2) seq->setL2(); 
@@ -267,7 +267,7 @@ TrigConf::HLTTEUtils::allTEsProducedInL2Chain( const TrigConf::HLTChain& chain,
    // get the input TEs
    set<string> inputTEs;
    for(set<string>::iterator outTEIt = l2tes.begin(); outTEIt != l2tes.end(); ++outTEIt) {
-      const TrigConf::HLTSequence* seq = sequenceList.getSequence(*outTEIt);
+      TrigConf::HLTSequence* seq = sequenceList.getSequence(*outTEIt);
       if(seq==0) {
          std::stringstream str;
          str << "TE " << *outTEIt << " is not produced by any sequence " << std::endl;
@@ -311,7 +311,7 @@ TrigConf::HLTTEUtils::allTEsProducedInEFChain( const TrigConf::HLTChain& chain,
    // get the input TEs
    set<string> inputTEs;
    for(set<string>::iterator outTEIt = eftes.begin(); outTEIt != eftes.end(); ++outTEIt) {
-      const TrigConf::HLTSequence* seq = sequenceList.getSequence(*outTEIt);
+      TrigConf::HLTSequence* seq = sequenceList.getSequence(*outTEIt);
       if(seq==0) {
          std::stringstream str;
          str << "TE " << *outTEIt << " is not produced by any sequence " << std::endl;
@@ -561,7 +561,7 @@ TrigConf::HLTTEUtils::mergeHLTChainList2( HLTFrame& frame) {
    
    // we need to keep the steps in sync so first we find the last step in L2
    unsigned int lastL2step(0);
-   for( TrigConf::HLTChain* chain : frame.chains() ) {
+   for( TrigConf::HLTChain* chain : frame.getHLTChainList() ) {
       if(chain->level_enum() != L2) continue;
       lastL2step = max(lastL2step, chain->lastStep());
    }
@@ -574,7 +574,7 @@ TrigConf::HLTTEUtils::mergeHLTChainList2( HLTFrame& frame) {
    // 5. merge the prescales, streams
 
    vector<HLTChain*> newHLTchains; 
-   for( TrigConf::HLTChain* chain : frame.chains() ) {
+   for( TrigConf::HLTChain* chain : frame.getHLTChainList() ) {
       if( chain->level_enum() != EF ) continue;
 
 
@@ -600,7 +600,7 @@ TrigConf::HLTTEUtils::mergeHLTChainList2( HLTFrame& frame) {
 
 
       // find the lower chain
-      const HLTChain * l2Chain = frame.chains().chain( hltChain->lower_chain_name() );
+      const HLTChain * l2Chain = frame.getHLTChainList().chain( hltChain->lower_chain_name() );
 
       // if no seeding l2 chain is found, nothing needs to be done
       if(l2Chain) {
diff --git a/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTFrame.h b/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTFrame.h
index 2e44959617bf279db8fcf02f3a9ade3d6b2c1a39..0e3aae779b72f716b906141089e90faf65f91016 100644
--- a/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTFrame.h
+++ b/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTFrame.h
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
 
 #ifndef TrigConf_HLTFrame
@@ -38,6 +38,7 @@ namespace TrigConf {
       /**@brief destructor*/
       ~HLTFrame();
 
+      /**@brief clear chains, sequences and prescales*/
       void clear();
 
       HLTChainList&                   theHLTChainList() { return m_HLTChainList; }    ///< accessor to the list of HLT chains
@@ -45,9 +46,7 @@ namespace TrigConf {
       HLTPrescaleSetCollection&       thePrescaleSetCollection() { return m_hltPrescaleSets; }
       HLTPrescaleSet*                 thePrescaleSet(unsigned int lbn=0) { return m_hltPrescaleSets.thePrescaleSet(lbn); }
 
-      const HLTChainList&             chains() const { return m_HLTChainList; }    ///< const accessor to the list of HLT chains
       const HLTChainList&             getHLTChainList() const { return m_HLTChainList; }    ///< const accessor to the list of HLT chains
-      const HLTSequenceList&          sequences() const { return m_HLTSequenceList; } ///< const accessor to the list of HLT sequences
       const HLTSequenceList&          getHLTSequenceList() const { return m_HLTSequenceList; } ///< const accessor to the list of HLT sequences
       const HLTPrescaleSetCollection& getPrescaleSetCollection() const { return m_hltPrescaleSets; }
       const HLTPrescaleSet*           getPrescaleSet() const { return m_hltPrescaleSets.prescaleSet(); }
@@ -70,12 +69,6 @@ namespace TrigConf {
       bool equals(const HLTFrame* other, const std::string& filename) const;
       DiffStruct* compareTo(const HLTFrame* o) const;
 
-
-      // for usage in python, since I can't bind HLTChainList due to boost multi_index dependency
-      std::vector<TrigConf::HLTChain*> chainsV() const;        ///< const accessor to the list of HLT chains as vector
-      std::vector<TrigConf::HLTSequence*> sequencesV() const; ///< const accessor to the list of HLT sequences as vector
-      std::string __str__() const;
-
    private:
 
       HLTChainList              m_HLTChainList;    ///< list of HLT trigger chains (owned)
diff --git a/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTSequence.h b/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTSequence.h
index 991d4feb54f291e677bae47e048483cce0fd7f17..52eb89d1c06a3dba2d7c08dc71da605f14953c2c 100644
--- a/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTSequence.h
+++ b/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTSequence.h
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
 
 #ifndef TrigConf_HLTSequence
@@ -67,11 +67,11 @@ namespace TrigConf {
 
       std::string concise() const;
 
-      void setL2(bool on=true) const { set(); if(on) m_level |= 0x1; else m_level &= 0x6; }
-      void setEF(bool on=true) const { set(); if(on) m_level |= 0x2; else m_level &= 0x5; }
-      void setHLT(bool on=true) const { set(); if(on) m_level = 0x4; else m_level &= 0x3; }
+      void setL2(bool on=true) { set(); if(on) m_level |= 0x1; else m_level &= 0x6; }
+      void setEF(bool on=true) { set(); if(on) m_level |= 0x2; else m_level &= 0x5; }
+      void setHLT(bool on=true) { set(); if(on) m_level = 0x4; else m_level &= 0x3; }
 
-      void reset() const { m_level = 0x8; }
+      void reset() { m_level = 0x8; }
       bool inL2() const { return (m_level&0x1) != 0; }
       bool inEF() const { return (m_level&0x2) != 0; }
       bool inHLT() const { return (m_level&0x4) != 0; }
@@ -94,9 +94,9 @@ namespace TrigConf {
       HLTTriggerElement*              m_topoStartTE { nullptr }; //!< only for topolical algorithms: specify output TE from previous topological Algo, for combinations
 
       // bit 0 - L2 / bit 1 - EF / bit 2 - HLT / bit 3 - unset
-      mutable unsigned int            m_level { 0 };      //!< level where sequence is running for a given configuration (to be determined in light of the menu, this
+      unsigned int            m_level { 0 };      //!< level where sequence is running for a given configuration (to be determined in light of the menu, this
                                                     //!< is not a property of the chain per se.) In rare cases a sequence could be running explicitely in both levels
-      void set() const { m_level &= 0x7; } 
+      void set() { m_level &= 0x7; }
                                              
       friend std::ostream & operator<<(std::ostream &, const HLTSequence &);
 
diff --git a/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTTriggerElement.h b/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTTriggerElement.h
index 40108c331f9036ea7b6823680ada4297f4af554d..080110f0bcfd71ee5f6885d9ed65ed093263e7e2 100644
--- a/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTTriggerElement.h
+++ b/Trigger/TrigConfiguration/TrigConfHLTData/TrigConfHLTData/HLTTriggerElement.h
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
 
 #ifndef TrigConf_HLTTriggerElement
@@ -69,9 +69,9 @@ namespace TrigConf {
       virtual void print(const std::string& indent="", unsigned int detail=1) const;
       virtual void writeXML(std::ofstream & xmlfile);
 
-      void setL2(bool on=true) const { set(); if(on) m_level |= 0x1; else m_level &= 0x2; }
-      void setEF(bool on=true) const { set(); if(on) m_level |= 0x2; else m_level &= 0x1; }
-      void reset() const { m_level = 0x4; }
+      void setL2(bool on=true) { set(); if(on) m_level |= 0x1; else m_level &= 0x2; }
+      void setEF(bool on=true) { set(); if(on) m_level |= 0x2; else m_level &= 0x1; }
+      void reset() { m_level = 0x4; }
       bool inL2() const { return (m_level&0x1) != 0; }
       bool inEF() const { return (m_level&0x2) != 0; }
       bool isSet() const { return (m_level&0x4) == 0; }
@@ -80,9 +80,9 @@ namespace TrigConf {
 
       unsigned int m_hashId;   ///< trigger element id  
 
-      mutable unsigned int m_level;      //!< level where TE is produced for a given configuration (to be determined in light of the menu, this
+      unsigned int m_level;      //!< level where TE is produced for a given configuration (to be determined in light of the menu, this
       //!< is not a property of the TE per se.) In rare cases a sequence could be running explicitely in both levels
-      void set() const { m_level &= 0x3; }
+      void set() { m_level &= 0x3; }
 
       friend std::ostream & operator<<(std::ostream &, const TrigConf::HLTTriggerElement &);
 
diff --git a/Trigger/TrigConfiguration/TrigConfStorage/src/ConfigurationCheck.cxx b/Trigger/TrigConfiguration/TrigConfStorage/src/ConfigurationCheck.cxx
index 8bdd8425104894a57534bcefcf21e3b4af40fb03..6279b8541152f3ce6c8f15ba4e8db6bd93873da7 100644
--- a/Trigger/TrigConfiguration/TrigConfStorage/src/ConfigurationCheck.cxx
+++ b/Trigger/TrigConfiguration/TrigConfStorage/src/ConfigurationCheck.cxx
@@ -1155,7 +1155,7 @@ public:
          }
       }
 
-      for( HLTChain* ch: m_hlt->chains() ) {
+      for( HLTChain* ch: m_hlt->getHLTChainList() ) {
 
          if( ch->level()=="EF" ) continue; // chains we do not care about in this check
          if( ch->lower_chain_name() == "") continue; // unseeded
diff --git a/Trigger/TrigConfiguration/TrigConfStorage/src/HLTFrameLoader.cxx b/Trigger/TrigConfiguration/TrigConfStorage/src/HLTFrameLoader.cxx
index 47074847cd67c12b15e6ca2814f7570998fa2bfd..3944ec241c57cbfb8259fe1a20c65ea9b4e91f2e 100755
--- a/Trigger/TrigConfiguration/TrigConfStorage/src/HLTFrameLoader.cxx
+++ b/Trigger/TrigConfiguration/TrigConfStorage/src/HLTFrameLoader.cxx
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
 
 #include "./HLTFrameLoader.h"
@@ -105,13 +105,13 @@ TrigConf::HLTFrameLoader::load( HLTFrame& frame ) {
       //merge chainlist
       if( frame.mergedHLT() ) {
         bool needMerging(false);
-        for( const TrigConf::HLTChain* chain : frame.chains() ) {
+        for( const TrigConf::HLTChain* chain : frame.getHLTChainList() ) {
           if(chain->level_enum() != TrigConf::HLT)
             needMerging = true;
         }
         
         if(needMerging) {
-          TRG_MSG_DEBUG("Call merging of " << frame.chains().size() << " L2 and EF chains");
+          TRG_MSG_DEBUG("Call merging of " << frame.getHLTChainList().size() << " L2 and EF chains");
           HLTTEUtils::mergeHLTChainList2(frame);
         }
       }
diff --git a/Trigger/TrigConfiguration/TrigConfStorage/src/XMLHLTFrameLoader.cxx b/Trigger/TrigConfiguration/TrigConfStorage/src/XMLHLTFrameLoader.cxx
index 5eacc7c0292af7b5765ad4556fa2baf788d5f1c5..50b0a905ac6acbd6ddd063678bf03abfffed9b0f 100755
--- a/Trigger/TrigConfiguration/TrigConfStorage/src/XMLHLTFrameLoader.cxx
+++ b/Trigger/TrigConfiguration/TrigConfStorage/src/XMLHLTFrameLoader.cxx
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
 
 #include "./XMLBoostHelper.h"
@@ -129,7 +129,7 @@ TrigConf::XMLHLTFrameLoader::buildHLTChainList( HLTFrame& frame ) {
    // assert that we don't have a mixed menu
    bool foundL2EFChain(false);
    bool foundHLTChain(false);
-   for( const TrigConf::HLTChain* chain : frame.chains() ) {
+   for( const TrigConf::HLTChain* chain : frame.getHLTChainList() ) {
       if(chain->level_enum() == TrigConf::HLT) {
          foundHLTChain = true;
       } else {
@@ -145,18 +145,18 @@ TrigConf::XMLHLTFrameLoader::buildHLTChainList( HLTFrame& frame ) {
    // merge chainlist if needed
    if( frame.mergedHLT() ) {
       bool needMerging(false);
-      for( const TrigConf::HLTChain* chain : frame.chains() ) {
+      for( const TrigConf::HLTChain* chain : frame.getHLTChainList() ) {
          if(chain->level_enum() != TrigConf::HLT)
             needMerging = true;
       }
 
       if(needMerging) {
-         TRG_MSG_DEBUG("Call merging of " << frame.chains().size() << " L2 and EF chains");
+         TRG_MSG_DEBUG("Call merging of " << frame.getHLTChainList().size() << " L2 and EF chains");
          HLTTEUtils::mergeHLTChainList2(frame);
       }
    }
 
-   TRG_MSG_INFO("Loaded " << frame.chains().size() << " chains");
+   TRG_MSG_INFO("Loaded " << frame.getHLTChainList().size() << " chains");
 
    //   std::cout<<"FPP: XMLHLTFrameLoader::load HLTFrame.mergedHLT() is " << nfTarget.mergedHLT() <<" and chainlist size is "<< nfTarget.getHLTChainList().chains() <<std::endl;
 
@@ -197,7 +197,7 @@ TrigConf::XMLHLTFrameLoader::buildHLTSequenceList( HLTFrame& frame ) {
       frame.theHLTSequenceList().addHLTSequence( aSeq );
    }
 
-   TRG_MSG_INFO("Loaded " << frame.sequences().size() << " sequences");
+   TRG_MSG_INFO("Loaded " << frame.getHLTSequenceList().size() << " sequences");
 
 }
 
diff --git a/Trigger/TrigConfiguration/TrigConfStorage/src/test/2COOLApp.cxx b/Trigger/TrigConfiguration/TrigConfStorage/src/test/2COOLApp.cxx
index 52ca3be086d258eb38937edd62a2a88094d331ff..b7dc0b2cfdde8c60c22874164dc9519d6781f30a 100755
--- a/Trigger/TrigConfiguration/TrigConfStorage/src/test/2COOLApp.cxx
+++ b/Trigger/TrigConfiguration/TrigConfStorage/src/test/2COOLApp.cxx
@@ -1,5 +1,5 @@
 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
 
 /////////////////////////////////////////////////////////////////////
@@ -863,7 +863,7 @@ int main( int argc, char* argv[] ) {
                    hltFrame.setSMK(masterConfigKey);
                    hltFrame.thePrescaleSetCollection().set_prescale_key_to_load(hltPrescaleKey);
                    sm->hltFrameLoader().load( hltFrame );
-                   hltpss = unique_ptr<TrigConf::HLTPrescaleSet>(hltFrame.chains().extractPrescaleSet());
+                   hltpss = unique_ptr<TrigConf::HLTPrescaleSet>(hltFrame.getHLTChainList().extractPrescaleSet());
                    cout << endl << *hltpss << endl;
                  }
                }
@@ -965,7 +965,7 @@ int main( int argc, char* argv[] ) {
                                            hltFrame,
                                            configSource);
 
-               unique_ptr<TrigConf::HLTPrescaleSet> hltpss(hltFrame.chains().extractPrescaleSet());
+               unique_ptr<TrigConf::HLTPrescaleSet> hltpss(hltFrame.getHLTChainList().extractPrescaleSet());
                coolWriter->writeHltPrescalePayload( runRanges, *hltpss.get());
                
                log << "Retrieving Lvl1 prescale set from " << lvl1ConfigXml << lineend;
diff --git a/Trigger/TrigConfiguration/TrigConfStorage/src/test/Run2toRun3ConvertersHLT.cxx b/Trigger/TrigConfiguration/TrigConfStorage/src/test/Run2toRun3ConvertersHLT.cxx
index 4cd45e01f635af2f1a3041fd761a5526addbbc81..bf65ca7cb83446dd4cde6fbfc937e6a4b99298ac 100644
--- a/Trigger/TrigConfiguration/TrigConfStorage/src/test/Run2toRun3ConvertersHLT.cxx
+++ b/Trigger/TrigConfiguration/TrigConfStorage/src/test/Run2toRun3ConvertersHLT.cxx
@@ -54,7 +54,7 @@ std::vector<std::string> l1thresholds(const TrigConf::HLTFrame* frame, const Tri
    std::set<std::string> names;
    for ( const auto sig: cptr->signatures() ) {
       for ( const auto te: sig->outputTEs() ) {
-         auto sequence = frame->sequences().getSequence(te->name());
+         auto sequence = frame->getHLTSequenceList().getSequence(te->name());
          for ( const auto inTE: sequence->inputTEs() ) {
             if ( not ( inTE->name().find("L2_") == 0 or inTE->name().find("EF_") == 0 or inTE->name().find("HLT_") == 0 ) ) {
                names.insert(inTE->name());
@@ -81,7 +81,7 @@ bool convertHLTMenu(const TrigConf::HLTFrame* frame, TrigConf::HLTMenu& menu) {
 
    std::map<std::string, const TrigConf::HLTStreamTag*> allStreams;
 
-   for ( auto cptr : frame->chains() ) {
+   for ( auto cptr : frame->getHLTChainList() ) {
       ptree pChain;
       pChain.put("counter", cptr->chain_counter());
       pChain.put("nameHash", cptr->chain_hash_id());
@@ -138,7 +138,7 @@ void convertRun2HLTPrescalesToRun3(const TrigConf::HLTFrame* frame, const std::s
    top.put("filetype", "hltprescale");
    top.put("name", frame->name());
    ptree pChains;
-   for ( auto cptr : frame->chains() ) {
+   for ( auto cptr : frame->getHLTChainList() ) {
       ptree pChain;
       pChain.put("name", cptr->chain_name());
       pChain.put("counter", cptr->chain_counter());
diff --git a/Trigger/TrigConfiguration/TrigConfigSvc/src/DSConfigSvc.cxx b/Trigger/TrigConfiguration/TrigConfigSvc/src/DSConfigSvc.cxx
index 97cd2b935e6c6646c1a904e1aa3ba39e733c669b..9556ad9ca5aec627ff7df5854c5541a73a5d1f83 100644
--- a/Trigger/TrigConfiguration/TrigConfigSvc/src/DSConfigSvc.cxx
+++ b/Trigger/TrigConfiguration/TrigConfigSvc/src/DSConfigSvc.cxx
@@ -334,7 +334,7 @@ TrigConf::DSConfigSvc::update ATLAS_NOT_THREAD_SAFE ( IOVSVC_CALLBACK_ARGS_K( ke
             nChains++;
          }
          ATH_MSG_INFO( "  Number of chains: " << nChains );
-         ATH_MSG_DEBUG( m_hltFrame.chains() );
+         ATH_MSG_DEBUG( m_hltFrame.getHLTChainList() );
       }
 
 
diff --git a/Trigger/TrigConfiguration/TrigConfigSvc/src/DSConfigSvc.h b/Trigger/TrigConfiguration/TrigConfigSvc/src/DSConfigSvc.h
index 98766e1776bca1955401498864bb32f53e0b9131..32b80a21976a7306805c16bfc796f5c141b3de96 100644
--- a/Trigger/TrigConfiguration/TrigConfigSvc/src/DSConfigSvc.h
+++ b/Trigger/TrigConfiguration/TrigConfigSvc/src/DSConfigSvc.h
@@ -86,12 +86,12 @@ namespace TrigConf {
 
       // access to HLT chains
       virtual const HLTChainList& chains() const override {
-         return m_hltFrame.chains();
+         return m_hltFrame.getHLTChainList();
       }
 
       // access to HLT sequences
       virtual const HLTSequenceList& sequences() const override {
-         return m_hltFrame.sequences();
+         return m_hltFrame.getHLTSequenceList();
       }
 
       // access to SMK
diff --git a/Trigger/TrigConfiguration/TrigConfigSvc/src/HLTConfigSvc.cxx b/Trigger/TrigConfiguration/TrigConfigSvc/src/HLTConfigSvc.cxx
index d56f3a1f75de5dc6aafec8766778deaadc201741..d14342b688ab7fe24051fe55b792547b42ecc9cb 100644
--- a/Trigger/TrigConfiguration/TrigConfigSvc/src/HLTConfigSvc.cxx
+++ b/Trigger/TrigConfiguration/TrigConfigSvc/src/HLTConfigSvc.cxx
@@ -172,11 +172,11 @@ HLTConfigSvc::initialize ATLAS_NOT_THREAD_SAFE() {
    // to do so, take the EF chain's lower_chain_name and loop through 
    // all L2 chains to find the matching chain_counter 
 
-   for( HLTChain* ch: m_HLTFrame.chains() ) {
+   for( HLTChain* ch: m_HLTFrame.getHLTChainList() ) {
       if( ch->level_enum() != EF ) continue;
       unsigned int lower_chain_counter = -1;
       if(ch->lower_chain_name() != "") {
-         HLTChain* lowerChain = m_HLTFrame.chains().chain(ch->lower_chain_name());
+         HLTChain* lowerChain = m_HLTFrame.getHLTChainList().chain(ch->lower_chain_name());
          if(lowerChain) lower_chain_counter = lowerChain->chain_counter();
       }
       ch->set_lower_chain_counter( lower_chain_counter );
diff --git a/Trigger/TrigConfiguration/TrigConfigSvc/src/TrigConfigSvc.cxx b/Trigger/TrigConfiguration/TrigConfigSvc/src/TrigConfigSvc.cxx
index 6e18872c36121b33a04eb034b01f2fa0542cc737..c6093d79d54ebc55056696c8d12a9f0ed3bed03e 100644
--- a/Trigger/TrigConfiguration/TrigConfigSvc/src/TrigConfigSvc.cxx
+++ b/Trigger/TrigConfiguration/TrigConfigSvc/src/TrigConfigSvc.cxx
@@ -199,7 +199,7 @@ TrigConfigSvc::chains() const {
       return m_hltservice->chains();
 
    REPORT_MESSAGE(MSG::WARNING) << "No HLT trigger configuration available" << endmsg;
-   return m_NullFrame.chains();
+   return m_NullFrame.getHLTChainList();
 }
 
 
@@ -209,7 +209,7 @@ TrigConfigSvc::sequences() const {
       return m_hltservice->sequences();
 
    REPORT_MESSAGE(MSG::WARNING) << "No HLT trigger configuration available" << endmsg;
-   return m_NullFrame.sequences();
+   return m_NullFrame.getHLTSequenceList();
 }