diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index ca0c11c5c..3f64627a7 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -6,7 +6,7 @@ on:
     - 'release/*'
   pull_request:
 env:
-  CORE_REPO_SHA: bce2aa649c9f3541a57b115ceb6694c5a00ca856
+  CORE_REPO_SHA: 5de7ffd7cbb555fb04d0138361a188496557080d
 
 jobs:
   build:
diff --git a/exporter/opentelemetry-exporter-datadog/CHANGELOG.md b/exporter/opentelemetry-exporter-datadog/CHANGELOG.md
index b7308e8e5..8011afc4b 100644
--- a/exporter/opentelemetry-exporter-datadog/CHANGELOG.md
+++ b/exporter/opentelemetry-exporter-datadog/CHANGELOG.md
@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+- Add fields method
+  ([#226](https://github.com/open-telemetry/opentelemetry-python/pull/226))
+
 ## Version 0.15b0
 
 Released 2020-11-02
diff --git a/exporter/opentelemetry-exporter-datadog/src/opentelemetry/exporter/datadog/propagator.py b/exporter/opentelemetry-exporter-datadog/src/opentelemetry/exporter/datadog/propagator.py
index ab1468c54..792659ade 100644
--- a/exporter/opentelemetry-exporter-datadog/src/opentelemetry/exporter/datadog/propagator.py
+++ b/exporter/opentelemetry-exporter-datadog/src/opentelemetry/exporter/datadog/propagator.py
@@ -106,6 +106,19 @@ class DatadogFormat(TextMapPropagator):
                 span.context.trace_state[constants.DD_ORIGIN],
             )
 
+    def fields(self):
+        """Returns a set with the fields set in `inject`.
+
+        See
+        `opentelemetry.trace.propagation.textmap.TextMapPropagator.fields`
+        """
+        return {
+            self.TRACE_ID_KEY,
+            self.PARENT_ID_KEY,
+            self.SAMPLING_PRIORITY_KEY,
+            self.ORIGIN_KEY,
+        }
+
 
 def format_trace_id(trace_id: int) -> str:
     """Format the trace id for Datadog."""
diff --git a/sdk-extension/opentelemetry-sdk-extension-aws/CHANGELOG.md b/sdk-extension/opentelemetry-sdk-extension-aws/CHANGELOG.md
index 33110ad86..1d218605a 100644
--- a/sdk-extension/opentelemetry-sdk-extension-aws/CHANGELOG.md
+++ b/sdk-extension/opentelemetry-sdk-extension-aws/CHANGELOG.md
@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+- Add method to return fields injected by propagator
+  ([#226](https://github.com/open-telemetry/opentelemetry-python/pull/226))
+
 ## Version 0.16b0
 
 Released 2020-11-25
diff --git a/sdk-extension/opentelemetry-sdk-extension-aws/src/opentelemetry/sdk/extension/aws/trace/propagation/aws_xray_format.py b/sdk-extension/opentelemetry-sdk-extension-aws/src/opentelemetry/sdk/extension/aws/trace/propagation/aws_xray_format.py
index c88877511..f9f4596e4 100644
--- a/sdk-extension/opentelemetry-sdk-extension-aws/src/opentelemetry/sdk/extension/aws/trace/propagation/aws_xray_format.py
+++ b/sdk-extension/opentelemetry-sdk-extension-aws/src/opentelemetry/sdk/extension/aws/trace/propagation/aws_xray_format.py
@@ -274,3 +274,12 @@ class AwsXRayFormat(TextMapPropagator):
         set_in_carrier(
             carrier, TRACE_HEADER_KEY, trace_header,
         )
+
+    def fields(self):
+        """Returns a set with the fields set in `inject`.
+
+        See
+        `opentelemetry.trace.propagation.textmap.TextMapPropagator.fields`
+        """
+
+        return {TRACE_HEADER_KEY}