diff --git a/pc/BUILD.gn b/pc/BUILD.gn
index 46bf22d..4962e75 100644
--- a/pc/BUILD.gn
+++ b/pc/BUILD.gn
@@ -2227,6 +2227,7 @@
       "peer_connection_data_channel_unittest.cc",
       "peer_connection_end_to_end_unittest.cc",
       "peer_connection_factory_unittest.cc",
+      "peer_connection_field_trial_tests.cc",
       "peer_connection_header_extension_unittest.cc",
       "peer_connection_histogram_unittest.cc",
       "peer_connection_ice_unittest.cc",
diff --git a/pc/peer_connection_field_trial_tests.cc b/pc/peer_connection_field_trial_tests.cc
new file mode 100644
index 0000000..528b6ba
--- /dev/null
+++ b/pc/peer_connection_field_trial_tests.cc
@@ -0,0 +1,191 @@
+/*
+ *  Copyright (c) 2022 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+// This file contains tests that verify that field trials do what they're
+// supposed to do.
+
+#include <set>
+
+#include "api/audio_codecs/builtin_audio_decoder_factory.h"
+#include "api/audio_codecs/builtin_audio_encoder_factory.h"
+#include "api/create_peerconnection_factory.h"
+#include "api/peer_connection_interface.h"
+#include "api/task_queue/default_task_queue_factory.h"
+#include "api/video_codecs/builtin_video_decoder_factory.h"
+#include "api/video_codecs/builtin_video_encoder_factory.h"
+#include "media/engine/webrtc_media_engine.h"
+#include "media/engine/webrtc_media_engine_defaults.h"
+#include "pc/peer_connection_wrapper.h"
+#include "pc/session_description.h"
+#include "pc/test/fake_audio_capture_module.h"
+#include "pc/test/peer_connection_test_wrapper.h"
+#include "rtc_base/internal/default_socket_server.h"
+#include "rtc_base/physical_socket_server.h"
+#include "rtc_base/thread.h"
+#include "test/gtest.h"
+#include "test/scoped_key_value_config.h"
+
+namespace webrtc {
+
+using RTCConfiguration = PeerConnectionInterface::RTCConfiguration;
+
+class PeerConnectionFieldTrialTest : public ::testing::Test {
+ protected:
+  typedef std::unique_ptr<PeerConnectionWrapper> WrapperPtr;
+
+  PeerConnectionFieldTrialTest()
+      : socket_server_(rtc::CreateDefaultSocketServer()),
+        main_thread_(socket_server_.get()) {
+    webrtc::PeerConnectionInterface::IceServer ice_server;
+    ice_server.uri = "stun:stun.l.google.com:19302";
+    config_.servers.push_back(ice_server);
+    config_.sdp_semantics = SdpSemantics::kUnifiedPlan;
+  }
+
+  void TearDown() override { pc_factory_ = nullptr; }
+
+  void CreatePCFactory(std::unique_ptr<FieldTrialsView> field_trials) {
+    PeerConnectionFactoryDependencies pcf_deps;
+    pcf_deps.signaling_thread = rtc::Thread::Current();
+    pcf_deps.worker_thread = rtc::Thread::Current();
+    pcf_deps.network_thread = rtc::Thread::Current();
+    pcf_deps.trials = std::move(field_trials);
+    pcf_deps.task_queue_factory = CreateDefaultTaskQueueFactory();
+    pcf_deps.call_factory = webrtc::CreateCallFactory();
+    cricket::MediaEngineDependencies media_deps;
+    media_deps.task_queue_factory = pcf_deps.task_queue_factory.get();
+    media_deps.adm = FakeAudioCaptureModule::Create();
+    media_deps.trials = pcf_deps.trials.get();
+    webrtc::SetMediaEngineDefaults(&media_deps);
+    pcf_deps.media_engine = cricket::CreateMediaEngine(std::move(media_deps));
+    pc_factory_ = CreateModularPeerConnectionFactory(std::move(pcf_deps));
+  }
+
+  WrapperPtr CreatePeerConnection() {
+    auto observer = std::make_unique<MockPeerConnectionObserver>();
+    auto result = pc_factory_->CreatePeerConnectionOrError(
+        config_, PeerConnectionDependencies(observer.get()));
+    RTC_CHECK(result.ok());
+
+    observer->SetPeerConnectionInterface(result.value().get());
+    return std::make_unique<PeerConnectionWrapper>(
+        pc_factory_, result.MoveValue(), std::move(observer));
+  }
+
+  std::unique_ptr<rtc::SocketServer> socket_server_;
+  rtc::AutoSocketServerThread main_thread_;
+  rtc::scoped_refptr<PeerConnectionFactoryInterface> pc_factory_ = nullptr;
+  webrtc::PeerConnectionInterface::RTCConfiguration config_;
+};
+
+// Tests for the dependency descriptor field trial. The dependency descriptor
+// field trial is implemented in media/engine/webrtc_video_engine.cc.
+TEST_F(PeerConnectionFieldTrialTest, EnableDependencyDescriptorAdvertised) {
+  std::unique_ptr<test::ScopedKeyValueConfig> field_trials =
+      std::make_unique<test::ScopedKeyValueConfig>(
+          "WebRTC-DependencyDescriptorAdvertised/Enabled/");
+  CreatePCFactory(std::move(field_trials));
+
+  WrapperPtr caller = CreatePeerConnection();
+  caller->AddTransceiver(cricket::MEDIA_TYPE_VIDEO);
+
+  auto offer = caller->CreateOffer();
+  auto contents1 = offer->description()->contents();
+  ASSERT_EQ(1u, contents1.size());
+
+  const cricket::MediaContentDescription* media_description1 =
+      contents1[0].media_description();
+  EXPECT_EQ(cricket::MEDIA_TYPE_VIDEO, media_description1->type());
+  const cricket::RtpHeaderExtensions& rtp_header_extensions1 =
+      media_description1->rtp_header_extensions();
+
+  bool found = absl::c_find_if(rtp_header_extensions1,
+                               [](const webrtc::RtpExtension& rtp_extension) {
+                                 return rtp_extension.uri ==
+                                        RtpExtension::kDependencyDescriptorUri;
+                               }) != rtp_header_extensions1.end();
+  EXPECT_TRUE(found);
+}
+
+// Tests that dependency descriptor RTP header extensions can be exchanged
+// via SDP munging, even if dependency descriptor field trial is disabled.
+TEST_F(PeerConnectionFieldTrialTest, InjectDependencyDescriptor) {
+  std::unique_ptr<test::ScopedKeyValueConfig> field_trials =
+      std::make_unique<test::ScopedKeyValueConfig>(
+          "WebRTC-DependencyDescriptorAdvertised/Disabled/");
+  CreatePCFactory(std::move(field_trials));
+
+  WrapperPtr caller = CreatePeerConnection();
+  WrapperPtr callee = CreatePeerConnection();
+  caller->AddTransceiver(cricket::MEDIA_TYPE_VIDEO);
+
+  auto offer = caller->CreateOffer();
+  cricket::ContentInfos& contents1 = offer->description()->contents();
+  ASSERT_EQ(1u, contents1.size());
+
+  cricket::MediaContentDescription* media_description1 =
+      contents1[0].media_description();
+  EXPECT_EQ(cricket::MEDIA_TYPE_VIDEO, media_description1->type());
+  cricket::RtpHeaderExtensions rtp_header_extensions1 =
+      media_description1->rtp_header_extensions();
+
+  bool found1 = absl::c_find_if(rtp_header_extensions1,
+                                [](const webrtc::RtpExtension& rtp_extension) {
+                                  return rtp_extension.uri ==
+                                         RtpExtension::kDependencyDescriptorUri;
+                                }) != rtp_header_extensions1.end();
+  EXPECT_FALSE(found1);
+
+  std::set<int> existing_ids;
+  for (const webrtc::RtpExtension& rtp_extension : rtp_header_extensions1) {
+    existing_ids.insert(rtp_extension.id);
+  }
+
+  // Find the currently unused RTP header extension ID.
+  int insert_id = 1;
+  std::set<int>::const_iterator iter = existing_ids.begin();
+  while (true) {
+    if (iter == existing_ids.end()) {
+      break;
+    }
+    if (*iter != insert_id) {
+      break;
+    }
+    insert_id++;
+    iter++;
+  }
+
+  rtp_header_extensions1.emplace_back(RtpExtension::kDependencyDescriptorUri,
+                                      insert_id);
+  media_description1->set_rtp_header_extensions(rtp_header_extensions1);
+
+  caller->SetLocalDescription(offer->Clone());
+
+  ASSERT_TRUE(callee->SetRemoteDescription(std::move(offer)));
+  auto answer = callee->CreateAnswer();
+
+  cricket::ContentInfos& contents2 = answer->description()->contents();
+  ASSERT_EQ(1u, contents2.size());
+
+  cricket::MediaContentDescription* media_description2 =
+      contents2[0].media_description();
+  EXPECT_EQ(cricket::MEDIA_TYPE_VIDEO, media_description2->type());
+  cricket::RtpHeaderExtensions rtp_header_extensions2 =
+      media_description2->rtp_header_extensions();
+
+  bool found2 = absl::c_find_if(rtp_header_extensions2,
+                                [](const webrtc::RtpExtension& rtp_extension) {
+                                  return rtp_extension.uri ==
+                                         RtpExtension::kDependencyDescriptorUri;
+                                }) != rtp_header_extensions2.end();
+  EXPECT_TRUE(found2);
+}
+
+}  // namespace webrtc