diff --git a/dart/biomechanics/SubjectOnDisk.cpp b/dart/biomechanics/SubjectOnDisk.cpp
index cfc6829c5..077ceab40 100644
--- a/dart/biomechanics/SubjectOnDisk.cpp
+++ b/dart/biomechanics/SubjectOnDisk.cpp
@@ -219,6 +219,40 @@ proto::BasicTrialType basicTrialTypeToProto(BasicTrialType type)
   return proto::BasicTrialType::other;
 }
 
+DataQuality dataQualityFromProto(proto::DataQuality quality)
+{
+  switch (quality)
+  {
+    case proto::DataQuality::pilotData:
+      return pilotData;
+    case proto::DataQuality::experimentalData:
+      return experimentalData;
+    case proto::DataQuality::internetData:
+      return internetData;
+    case proto::DataQuality_INT_MIN_SENTINEL_DO_NOT_USE_:
+      return internetData;
+      break;
+    case proto::DataQuality_INT_MAX_SENTINEL_DO_NOT_USE_:
+      return internetData;
+      break;
+  }
+  return internetData;
+}
+
+proto::DataQuality dataQualityToProto(DataQuality quality)
+{
+  switch (quality)
+  {
+    case pilotData:
+      return proto::DataQuality::pilotData;
+    case experimentalData:
+      return proto::DataQuality::experimentalData;
+    case internetData:
+      return proto::DataQuality::internetData;
+  }
+  return proto::DataQuality::pilotData;
+}
+
 DetectedTrialFeature detectedTrialFeatureFromProto(
     proto::DetectedTrialFeature feature)
 {
@@ -1568,6 +1602,12 @@ std::vector<MissingGRFReason> SubjectOnDisk::getMissingGRF(int trial)
   return mHeader->mTrials[trial]->mMissingGRFReason;
 }
 
+/// This returns the user supplied enum of type 'DataQuality'
+DataQuality SubjectOnDisk::getQuality()
+{
+  return mHeader->getQuality();
+}
+
 int SubjectOnDisk::getNumProcessingPasses()
 {
   return mHeader->mPasses.size();
@@ -3680,6 +3720,17 @@ SubjectOnDiskHeader& SubjectOnDiskHeader::setNotes(const std::string& notes)
   return *this;
 }
 
+SubjectOnDiskHeader& SubjectOnDiskHeader::setQuality(DataQuality quality)
+{
+  mDataQuality = quality;
+  return *this;
+}
+
+DataQuality SubjectOnDiskHeader::getQuality()
+{
+  return mDataQuality;
+}
+
 std::shared_ptr<SubjectOnDiskPassHeader>
 SubjectOnDiskHeader::addProcessingPass()
 {
@@ -3915,6 +3966,7 @@ void SubjectOnDiskHeader::write(dart::proto::SubjectOnDiskHeader* header)
   {
     header->add_exo_dof_index(index);
   }
+  header->set_data_quality(dataQualityToProto(mDataQuality));
 
   if (!header->IsInitialized())
   {
@@ -4059,6 +4111,8 @@ void SubjectOnDiskHeader::read(const dart::proto::SubjectOnDiskHeader& proto)
   {
     mExoDofIndices.push_back(proto.exo_dof_index(i));
   }
+
+  mDataQuality = dataQualityFromProto(proto.data_quality());
 }
 
 void SubjectOnDiskHeader::writeSensorsFrame(
diff --git a/dart/biomechanics/SubjectOnDisk.hpp b/dart/biomechanics/SubjectOnDisk.hpp
index fae66f9b0..3bcb4619b 100644
--- a/dart/biomechanics/SubjectOnDisk.hpp
+++ b/dart/biomechanics/SubjectOnDisk.hpp
@@ -463,6 +463,8 @@ class SubjectOnDiskHeader
   SubjectOnDiskHeader& setSubjectTags(std::vector<std::string> subjectTags);
   SubjectOnDiskHeader& setHref(const std::string& sourceHref);
   SubjectOnDiskHeader& setNotes(const std::string& notes);
+  SubjectOnDiskHeader& setQuality(DataQuality quality);
+  DataQuality getQuality();
   std::shared_ptr<SubjectOnDiskPassHeader> addProcessingPass();
   std::vector<std::shared_ptr<SubjectOnDiskPassHeader>> getProcessingPasses();
   std::shared_ptr<SubjectOnDiskTrial> addTrial();
@@ -522,6 +524,9 @@ class SubjectOnDiskHeader
   // This is exoskeleton data
   std::vector<int> mExoDofIndices;
 
+  // This is the user supplied quality of the data
+  DataQuality mDataQuality;
+
   friend class SubjectOnDisk;
   friend struct Frame;
   friend struct FramePass;
@@ -637,6 +642,9 @@ class SubjectOnDisk
   /// include `notMissingGRF`.
   std::vector<MissingGRFReason> getMissingGRF(int trial);
 
+  /// This returns the user supplied enum of type 'DataQuality'
+  DataQuality getQuality();
+
   int getNumProcessingPasses();
 
   ProcessingPassType getProcessingPassType(int processingPass);
diff --git a/dart/biomechanics/enums.hpp b/dart/biomechanics/enums.hpp
index 6a66ac0f8..5b8ad9b47 100644
--- a/dart/biomechanics/enums.hpp
+++ b/dart/biomechanics/enums.hpp
@@ -45,6 +45,13 @@ enum DetectedTrialFeature
   flatTerrain
 };
 
+enum DataQuality
+{
+  pilotData,
+  experimentalData,
+  internetData
+};
+
 enum MissingGRFStatus
 {
   no = 0,      // no will cast to `false`
diff --git a/dart/proto/SubjectOnDisk.proto b/dart/proto/SubjectOnDisk.proto
index f82103276..80463e40b 100644
--- a/dart/proto/SubjectOnDisk.proto
+++ b/dart/proto/SubjectOnDisk.proto
@@ -44,6 +44,12 @@ enum DetectedTrialFeature {
   flatTerrain = 3;
 }
 
+enum DataQuality {
+  pilotData = 0;
+  experimentalData = 1;
+  internetData = 2;
+}
+
 // Many of the ML tasks we want to support from SubjectOnDisk data include 
 // effectively predicting the results of a downstream processing task from 
 // an upstream processing task. Trivially, that's predicting physics from
@@ -166,6 +172,8 @@ message SubjectOnDiskHeader {
   repeated int32 exo_dof_index = 22;
   // Details about the subject tags provided on the AddBiomechanics platform
   repeated string subject_tag = 23;
+  // This is what the user has tagged this subject as, in terms of data quality
+  DataQuality data_quality = 25;
 }
 
 message SubjectOnDiskProcessingPassFrame {
diff --git a/python/_nimblephysics/biomechanics/SubjectOnDisk.cpp b/python/_nimblephysics/biomechanics/SubjectOnDisk.cpp
index 1a82aa0aa..6e13db8e8 100644
--- a/python/_nimblephysics/biomechanics/SubjectOnDisk.cpp
+++ b/python/_nimblephysics/biomechanics/SubjectOnDisk.cpp
@@ -73,6 +73,21 @@ void SubjectOnDisk(py::module& m)
                 "This is a trial that doesn't fit into any of the "
                 "other categories.");
 
+  auto dataQuality
+      = ::py::enum_<dart::biomechanics::DataQuality>(m, "DataQuality")
+            .value(
+                "PILOT_DATA",
+                dart::biomechanics::DataQuality::pilotData,
+                "This is data that was collected as part of a pilot study.")
+            .value(
+                "EXPERIMENTAL_DATA",
+                dart::biomechanics::DataQuality::experimentalData,
+                "This is data that was collected as part of an experiment.")
+            .value(
+                "INTERNET_DATA",
+                dart::biomechanics::DataQuality::internetData,
+                "This is data that was collected from the internet.");
+
   auto detectedTrialFeature
       = ::py::enum_<dart::biomechanics::DetectedTrialFeature>(
             m, "DetectedTrialFeature")
@@ -1089,6 +1104,13 @@ Note that these are specified in the local body frame, acting on the body at its
                 "setNotes",
                 &dart::biomechanics::SubjectOnDiskHeader::setNotes,
                 ::py::arg("notes"))
+            .def(
+                "setQuality",
+                &dart::biomechanics::SubjectOnDiskHeader::setQuality,
+                ::py::arg("quality"))
+            .def(
+                "getQuality",
+                &dart::biomechanics::SubjectOnDiskHeader::getQuality)
             .def(
                 "addProcessingPass",
                 &dart::biomechanics::SubjectOnDiskHeader::addProcessingPass)
@@ -1323,6 +1345,11 @@ Note that these are specified in the local body frame, acting on the body at its
             This method is provided to give a cheaper way to filter out frames we want to ignore for training, without having to call
             the more expensive :code:`loadFrames()` and examine frames individually.
           )doc")
+            .def(
+                "getQuality",
+                &dart::biomechanics::SubjectOnDisk::getQuality,
+                "This returns the user-supplied quality of the data in this "
+                "subject")
             //   int getNumProcessingPasses();
             .def(
                 "getNumProcessingPasses",