diff --git a/roofit/histfactory/inc/RooStats/HistFactory/Detail/HistFactoryImpl.h b/roofit/histfactory/inc/RooStats/HistFactory/Detail/HistFactoryImpl.h
index 02e0846e76dda..744726f506972 100644
--- a/roofit/histfactory/inc/RooStats/HistFactory/Detail/HistFactoryImpl.h
+++ b/roofit/histfactory/inc/RooStats/HistFactory/Detail/HistFactoryImpl.h
@@ -13,15 +13,24 @@
 #ifndef HistFactoryImplHelpers_h
 #define HistFactoryImplHelpers_h
 
-#include <RooStats/HistFactory/Measurement.h>
-
 #include <RooGlobalFunc.h>
 #include <RooWorkspace.h>
 
 #include <ROOT/RSpan.hxx>
 
-namespace RooStats {
-namespace HistFactory {
+namespace RooStats::HistFactory {
+
+namespace Constraint {
+
+enum Type {
+   Gaussian,
+   Poisson
+};
+std::string Name(Type type);
+Type GetType(const std::string &Name);
+
+} // namespace Constraint
+
 namespace Detail {
 
 namespace MagicConstants {
@@ -49,15 +58,13 @@ void configureConstrainedGammas(RooArgList const &gammas, std::span<const double
 
 struct CreateGammaConstraintsOutput {
    std::vector<std::unique_ptr<RooAbsPdf>> constraints;
-   std::vector<RooRealVar*> globalObservables;
+   std::vector<RooRealVar *> globalObservables;
 };
 
-CreateGammaConstraintsOutput createGammaConstraints(RooArgList const &paramList,
-                                                    std::span<const double> relSigmas, double minSigma,
-                                                    Constraint::Type type);
+CreateGammaConstraintsOutput createGammaConstraints(RooArgList const &paramList, std::span<const double> relSigmas,
+                                                    double minSigma, Constraint::Type type);
 
 } // namespace Detail
-} // namespace HistFactory
-} // namespace RooStats
+} // namespace RooStats::HistFactory
 
 #endif
diff --git a/roofit/histfactory/inc/RooStats/HistFactory/Measurement.h b/roofit/histfactory/inc/RooStats/HistFactory/Measurement.h
index 8c8cf30dc0bd8..1389c5615f6ef 100644
--- a/roofit/histfactory/inc/RooStats/HistFactory/Measurement.h
+++ b/roofit/histfactory/inc/RooStats/HistFactory/Measurement.h
@@ -13,6 +13,8 @@
 
 #include <TNamed.h>
 
+#include <RooStats/HistFactory/Detail/HistFactoryImpl.h>
+
 #include <fstream>
 #include <iostream>
 #include <map>
@@ -27,17 +29,6 @@ class RooWorkspace;
 
 namespace RooStats::HistFactory {
 
-namespace Constraint {
-
-enum Type {
-   Gaussian,
-   Poisson
-};
-std::string Name(Type type);
-Type GetType(const std::string &Name);
-
-} // namespace Constraint
-
 /** \class OverallSys
  * \ingroup HistFactory
  * Configuration for a constrained overall systematic to scale sample normalisations.
@@ -257,12 +248,24 @@ class ShapeFactor : public HistogramUncertaintyBase {
    }
    const std::string &GetHistoPath() const { return fHistoPathHigh; }
 
+   double GetVal() const { return fValue; }
+
+   double GetMin() const { return fMinVal; }
+   double GetMax() const { return fMaxVal; }
+
+   void SetVal(double value) { fValue = value; }
+
+   void SetMin(double minVal) { fMinVal = minVal; }
+   void SetMax(double maxVal) { fMaxVal = maxVal; }
+
 protected:
    bool fConstant = false;
-
-   // A histogram representing
-   // the initial shape
    bool fHasInitialShape = false;
+   double fValue = 1.0;
+   // GHL: Again, we are putting hard ranges on the gammas by default.
+   //      We should change this to range from 0 to /inf.
+   double fMinVal = Detail::MagicConstants::defaultGammaMin;
+   double fMaxVal = Detail::MagicConstants::defaultShapeFactorGammaMax;
 };
 
 /** \class StatError
@@ -484,6 +487,7 @@ class Sample {
    void AddHistoFactor(const HistoFactor &Factor);
 
    void AddShapeFactor(std::string Name);
+   void AddShapeFactor(std::string Name, double initialVal, double minVal, double maxVal);
    void AddShapeFactor(const ShapeFactor &Factor);
 
    void AddShapeSys(std::string Name, Constraint::Type ConstraintType, std::string HistoName, std::string HistoFile,
diff --git a/roofit/histfactory/src/ConfigParser.cxx b/roofit/histfactory/src/ConfigParser.cxx
index 54a937b8cae15..b4776a4fbe748 100644
--- a/roofit/histfactory/src/ConfigParser.cxx
+++ b/roofit/histfactory/src/ConfigParser.cxx
@@ -1253,6 +1253,15 @@ HistFactory::ShapeFactor ConfigParser::MakeShapeFactor( TXMLNode* node ) {
     else if( attrName == TString( "Name" ) ) {
       shapeFactor.SetName( attrVal );
     }
+    else if( attrName == TString( "Val" ) ) {
+      shapeFactor.SetVal( toDouble(attrVal) );
+    }
+    else if( attrName == TString( "Min" ) ) {
+      shapeFactor.SetMin( toDouble(attrVal) );
+    }
+    else if( attrName == TString( "Max" ) ) {
+      shapeFactor.SetMax( toDouble(attrVal) );
+    }
     else if( attrName == TString( "Const" ) ) {
       shapeFactor.SetConstant( CheckTrueFalse(attrVal, "ShapeFactor" ) );
     }
diff --git a/roofit/histfactory/src/HistoToWorkspaceFactoryFast.cxx b/roofit/histfactory/src/HistoToWorkspaceFactoryFast.cxx
index a1b72e95f6c90..6268188ddde24 100644
--- a/roofit/histfactory/src/HistoToWorkspaceFactoryFast.cxx
+++ b/roofit/histfactory/src/HistoToWorkspaceFactoryFast.cxx
@@ -1032,13 +1032,18 @@ RooArgList HistoToWorkspaceFactoryFast::createObservables(const TH1 *hist, RooWo
               }
 
               // Create the Parameters
-              std::string funcParams = "gamma_" + shapeFactor.GetName();
-
-              // GHL: Again, we are putting hard ranges on the gamma's
-              //      We should change this to range from 0 to /inf
               RooArgList shapeFactorParams = ParamHistFunc::createParamSet(proto,
-                  funcParams,
-                  theObservables, defaultGammaMin, defaultShapeFactorGammaMax);
+                  "gamma_" + shapeFactor.GetName(),
+                  theObservables);
+              for (auto *comp : shapeFactorParams) {
+                // If the gamma is subject to a preprocess function, it is a RooAbsReal and
+                // we don't need to set the initial value.
+                if(auto var = dynamic_cast<RooRealVar*>(comp)) {
+                  var->setVal(shapeFactor.GetVal());
+                  var->setMin(shapeFactor.GetMin());
+                  var->setMax(shapeFactor.GetMax());
+                }
+              }
 
               // Create the Function
               ParamHistFunc shapeFactorFunc( funcName.c_str(), funcName.c_str(),
diff --git a/roofit/histfactory/src/Measurement.cxx b/roofit/histfactory/src/Measurement.cxx
index bc7b84e43e673..6fc74fba160b7 100644
--- a/roofit/histfactory/src/Measurement.cxx
+++ b/roofit/histfactory/src/Measurement.cxx
@@ -994,9 +994,18 @@ void Sample::AddHistoFactor(const HistoFactor &Factor)
 void Sample::AddShapeFactor(std::string SysName)
 {
 
-   ShapeFactor factor;
-   factor.SetName(SysName);
-   fShapeFactorList.push_back(factor);
+   fShapeFactorList.emplace_back();
+   fShapeFactorList.back().SetName(SysName);
+}
+
+void Sample::AddShapeFactor(std::string SysName, double value, double minVal, double maxVal)
+{
+
+   fShapeFactorList.emplace_back();
+   fShapeFactorList.back().SetName(SysName);
+   fShapeFactorList.back().SetVal(value);
+   fShapeFactorList.back().SetMin(minVal);
+   fShapeFactorList.back().SetMax(maxVal);
 }
 
 void Sample::AddShapeFactor(const ShapeFactor &Factor)
@@ -1904,6 +1913,8 @@ void ShapeFactor::Print(std::ostream &stream) const
              << " Shape Hist Name: " << fHistoNameHigh << " Shape Hist Path Name: " << fHistoPathHigh
              << " Shape Hist FileName: " << fInputFileHigh << std::endl;
    }
+   // Print value and range in RooRealVar style
+   stream << "\t \t Value: " << GetVal() << "  L(" << GetMin() << " - " << GetMax() << ")\n";
 
    if (fConstant) {
       stream << "\t \t ( Constant ): " << std::endl;
@@ -1937,6 +1948,9 @@ void ShapeFactor::PrintXML(std::ostream &xml) const
           << " HistoName=\"" << GetHistoName() << "\" "
           << " HistoPath=\"" << GetHistoPath() << "\" ";
    }
+   xml << " Value=\"" << GetVal() << "\" "
+       << " Min=\"" << GetMin() << "\" "
+       << " Max=\"" << GetMax() << "\" ";
    xml << "  /> " << std::endl;
 }