diff --git a/api/umametrics.h b/api/umametrics.h
index 2347ac2..71a3d5e 100644
--- a/api/umametrics.h
+++ b/api/umametrics.h
@@ -38,6 +38,8 @@
   kEnumCounterIceRegathering,
   kEnumCounterIceRestart,
   kEnumCounterKeyProtocol,
+  kEnumCounterSdpSemanticRequested,
+  kEnumCounterSdpSemanticNegotiated,
   kPeerConnectionEnumCounterMax
 };
 
@@ -118,6 +120,21 @@
   kEnumCounterKeyProtocolMax
 };
 
+enum SdpSemanticRequested {
+  kSdpSemanticRequestDefault,
+  kSdpSemanticRequestPlanB,
+  kSdpSemanticRequestUnifiedPlan,
+  kSdpSemanticRequestMax
+};
+
+enum SdpSemanticNegotiated {
+  kSdpSemanticNegotiatedNone,
+  kSdpSemanticNegotiatedPlanB,
+  kSdpSemanticNegotiatedUnifiedPlan,
+  kSdpSemanticNegotiatedMixed,
+  kSdpSemanticNegotiatedMax
+};
+
 class MetricsObserverInterface : public rtc::RefCountInterface {
  public:
   // |type| is the type of the enum counter to be incremented. |counter|
diff --git a/pc/peerconnection.cc b/pc/peerconnection.cc
index 14c2a88..1bdd640 100644
--- a/pc/peerconnection.cc
+++ b/pc/peerconnection.cc
@@ -1976,6 +1976,34 @@
     network_thread()->Invoke<void>(
         RTC_FROM_HERE, rtc::Bind(&cricket::PortAllocator::DiscardCandidatePool,
                                  port_allocator_.get()));
+    // Make UMA notes about what was agreed to.
+    if (uma_observer_) {
+      switch (remote_description()->description()->msid_signaling()) {
+        case 0:
+          uma_observer_->IncrementEnumCounter(kEnumCounterSdpSemanticNegotiated,
+                                              kSdpSemanticNegotiatedNone,
+                                              kSdpSemanticNegotiatedMax);
+          break;
+        case cricket::kMsidSignalingMediaSection:
+          uma_observer_->IncrementEnumCounter(kEnumCounterSdpSemanticNegotiated,
+                                              kSdpSemanticNegotiatedUnifiedPlan,
+                                              kSdpSemanticNegotiatedMax);
+          break;
+        case cricket::kMsidSignalingSsrcAttribute:
+          uma_observer_->IncrementEnumCounter(kEnumCounterSdpSemanticNegotiated,
+                                              kSdpSemanticNegotiatedPlanB,
+                                              kSdpSemanticNegotiatedMax);
+          break;
+        case cricket::kMsidSignalingMediaSection |
+            cricket::kMsidSignalingSsrcAttribute:
+          uma_observer_->IncrementEnumCounter(kEnumCounterSdpSemanticNegotiated,
+                                              kSdpSemanticNegotiatedMixed,
+                                              kSdpSemanticNegotiatedMax);
+          break;
+        default:
+          RTC_NOTREACHED();
+      }
+    }
   }
 
   observer->OnSetRemoteDescriptionComplete(RTCError::OK());
@@ -2675,6 +2703,27 @@
           kEnumCounterAddressFamily, kPeerConnection_IPv4,
           kPeerConnectionAddressFamilyCounter_Max);
     }
+    // Send information about the requested SDP semantics.
+    switch (configuration_.sdp_semantics) {
+      case SdpSemantics::kDefault:
+        uma_observer_->IncrementEnumCounter(kEnumCounterSdpSemanticRequested,
+                                            kSdpSemanticRequestDefault,
+                                            kSdpSemanticRequestMax);
+
+        break;
+      case SdpSemantics::kPlanB:
+        uma_observer_->IncrementEnumCounter(kEnumCounterSdpSemanticRequested,
+                                            kSdpSemanticRequestPlanB,
+                                            kSdpSemanticRequestMax);
+        break;
+      case SdpSemantics::kUnifiedPlan:
+        uma_observer_->IncrementEnumCounter(kEnumCounterSdpSemanticRequested,
+                                            kSdpSemanticRequestUnifiedPlan,
+                                            kSdpSemanticRequestMax);
+        break;
+      default:
+        RTC_NOTREACHED();
+    }
   }
 }
 
diff --git a/pc/peerconnection_rtp_unittest.cc b/pc/peerconnection_rtp_unittest.cc
index 023ce92..2f20261 100644
--- a/pc/peerconnection_rtp_unittest.cc
+++ b/pc/peerconnection_rtp_unittest.cc
@@ -13,6 +13,7 @@
 
 #include "api/audio_codecs/builtin_audio_decoder_factory.h"
 #include "api/audio_codecs/builtin_audio_encoder_factory.h"
+#include "api/fakemetricsobserver.h"
 #include "api/jsep.h"
 #include "api/mediastreaminterface.h"
 #include "api/peerconnectioninterface.h"
@@ -889,6 +890,9 @@
   caller->AddAudioTrack("caller_audio");
   auto callee = CreatePeerConnectionWithUnifiedPlan();
   callee->AddAudioTrack("callee_audio");
+  auto caller_observer =
+      new rtc::RefCountedObject<webrtc::FakeMetricsObserver>();
+  caller->pc()->RegisterUMAObserver(caller_observer);
 
   ASSERT_TRUE(caller->ExchangeOfferAnswerWith(callee.get()));
 
@@ -902,6 +906,19 @@
   auto* answer = caller->pc()->remote_description();
   EXPECT_EQ(cricket::kMsidSignalingMediaSection,
             answer->description()->msid_signaling());
+  // Check that this is counted correctly
+  EXPECT_EQ(1, caller_observer->GetEnumCounter(
+                   webrtc::kEnumCounterSdpSemanticNegotiated,
+                   webrtc::kSdpSemanticNegotiatedUnifiedPlan));
+  EXPECT_EQ(0, caller_observer->GetEnumCounter(
+                   webrtc::kEnumCounterSdpSemanticNegotiated,
+                   webrtc::kSdpSemanticNegotiatedNone));
+  EXPECT_EQ(0, caller_observer->GetEnumCounter(
+                   webrtc::kEnumCounterSdpSemanticNegotiated,
+                   webrtc::kSdpSemanticNegotiatedPlanB));
+  EXPECT_EQ(0, caller_observer->GetEnumCounter(
+                   webrtc::kEnumCounterSdpSemanticNegotiated,
+                   webrtc::kSdpSemanticNegotiatedMixed));
 }
 
 TEST_F(PeerConnectionMsidSignalingTest, PlanBOfferToUnifiedPlanAnswer) {