diff --git a/api/field_trials_unittest.cc b/api/field_trials_unittest.cc
index 213ca2db86..082222cee1 100644
--- a/api/field_trials_unittest.cc
+++ b/api/field_trials_unittest.cc
@@ -10,8 +10,11 @@
 
 #include "api/field_trials.h"
 
+#include <memory>
+
 #include "api/transport/field_trial_based_config.h"
 #include "system_wrappers/include/field_trial.h"
+#include "test/gmock.h"
 #include "test/gtest.h"
 
 #if GTEST_HAS_DEATH_TEST && !defined(WEBRTC_ANDROID)
@@ -19,67 +22,79 @@
 #endif  // GTEST_HAS_DEATH_TEST && !defined(WEBRTC_ANDROID)
 
 namespace webrtc {
+namespace {
 
-TEST(FieldTrials, EmptyString) {
+using ::testing::NotNull;
+
+TEST(FieldTrialsTest, EmptyStringHasNoEffect) {
   FieldTrials f("");
   EXPECT_FALSE(f.IsEnabled("MyCoolTrial"));
   EXPECT_FALSE(f.IsDisabled("MyCoolTrial"));
 }
 
-TEST(FieldTrials, EnableDisable) {
-  FieldTrials f("MyCoolTrial/Enabled/MyUncoolTrial/Disabled/");
+TEST(FieldTrialsTest, EnabledDisabledMustBeFirstInValue) {
+  FieldTrials f(
+      "MyCoolTrial/EnabledFoo/"
+      "MyUncoolTrial/DisabledBar/"
+      "AnotherTrial/BazEnabled/");
   EXPECT_TRUE(f.IsEnabled("MyCoolTrial"));
   EXPECT_TRUE(f.IsDisabled("MyUncoolTrial"));
+  EXPECT_FALSE(f.IsEnabled("AnotherTrial"));
 }
 
-TEST(FieldTrials, SetGlobalStringAndReadFromFieldTrial) {
-  const char* s = "MyCoolTrial/Enabled/MyUncoolTrial/Disabled/";
+TEST(FieldTrialsTest, FieldTrialsDoesNotReadGlobalString) {
+  static constexpr char s[] = "MyCoolTrial/Enabled/MyUncoolTrial/Disabled/";
   webrtc::field_trial::InitFieldTrialsFromString(s);
-  FieldTrialBasedConfig f;
-  EXPECT_TRUE(f.IsEnabled("MyCoolTrial"));
-  EXPECT_TRUE(f.IsDisabled("MyUncoolTrial"));
+  FieldTrials f("");
+  EXPECT_FALSE(f.IsEnabled("MyCoolTrial"));
+  EXPECT_FALSE(f.IsDisabled("MyUncoolTrial"));
 }
 
-TEST(FieldTrials, SetFieldTrialAndReadFromGlobalString) {
+TEST(FieldTrialsTest, FieldTrialsWritesGlobalString) {
   FieldTrials f("MyCoolTrial/Enabled/MyUncoolTrial/Disabled/");
   EXPECT_TRUE(webrtc::field_trial::IsEnabled("MyCoolTrial"));
   EXPECT_TRUE(webrtc::field_trial::IsDisabled("MyUncoolTrial"));
 }
 
-TEST(FieldTrials, RestoresGlobalString) {
-  const char* s = "SomeString/Enabled/";
+TEST(FieldTrialsTest, FieldTrialsRestoresGlobalStringAfterDestruction) {
+  static constexpr char s[] = "SomeString/Enabled/";
   webrtc::field_trial::InitFieldTrialsFromString(s);
   {
     FieldTrials f("SomeOtherString/Enabled/");
-    EXPECT_EQ(std::string("SomeOtherString/Enabled/"),
-              webrtc::field_trial::GetFieldTrialString());
+    EXPECT_STREQ(webrtc::field_trial::GetFieldTrialString(),
+                 "SomeOtherString/Enabled/");
   }
-  EXPECT_EQ(s, webrtc::field_trial::GetFieldTrialString());
+  EXPECT_STREQ(webrtc::field_trial::GetFieldTrialString(), s);
 }
 
 #if GTEST_HAS_DEATH_TEST && !defined(WEBRTC_ANDROID)
-TEST(FieldTrials, OnlyOneInstance) {
+TEST(FieldTrialsTest, FieldTrialsDoesNotSupportSimultaneousInstances) {
   FieldTrials f("SomeString/Enabled/");
   RTC_EXPECT_DEATH(FieldTrials("SomeOtherString/Enabled/").Lookup("Whatever"),
                    "Only one instance");
 }
 #endif  // GTEST_HAS_DEATH_TEST && !defined(WEBRTC_ANDROID)
 
-TEST(FieldTrials, SequentialInstances) {
+TEST(FieldTrialsTest, FieldTrialsSupportsSeparateInstances) {
   { FieldTrials f("SomeString/Enabled/"); }
   { FieldTrials f("SomeOtherString/Enabled/"); }
 }
 
-TEST(FieldTrials, NoGlobals) {
-  auto f1 = FieldTrials::CreateNoGlobal("SomeString/Enabled/");
-  EXPECT_TRUE(f1);
+TEST(FieldTrialsTest, NonGlobalFieldTrialsInstanceDoesNotModifyGlobalString) {
+  std::unique_ptr<FieldTrials> f =
+      FieldTrials::CreateNoGlobal("SomeString/Enabled/");
+  ASSERT_THAT(f, NotNull());
+  EXPECT_TRUE(f->IsEnabled("SomeString"));
+  EXPECT_FALSE(webrtc::field_trial::IsEnabled("SomeString"));
 }
 
-TEST(FieldTrials, SeveralNoGlobals) {
-  auto f1 = FieldTrials::CreateNoGlobal("SomeString/Enabled/");
-  auto f2 = FieldTrials::CreateNoGlobal("SomeOtherString/Enabled/");
-  ASSERT_TRUE(f1);
-  ASSERT_TRUE(f2);
+TEST(FieldTrialsTest, NonGlobalFieldTrialsSupportSimultaneousInstances) {
+  std::unique_ptr<FieldTrials> f1 =
+      FieldTrials::CreateNoGlobal("SomeString/Enabled/");
+  std::unique_ptr<FieldTrials> f2 =
+      FieldTrials::CreateNoGlobal("SomeOtherString/Enabled/");
+  ASSERT_THAT(f1, NotNull());
+  ASSERT_THAT(f2, NotNull());
 
   EXPECT_TRUE(f1->IsEnabled("SomeString"));
   EXPECT_FALSE(f1->IsEnabled("SomeOtherString"));
@@ -88,16 +103,26 @@ TEST(FieldTrials, SeveralNoGlobals) {
   EXPECT_TRUE(f2->IsEnabled("SomeOtherString"));
 }
 
-TEST(FieldTrials, GlobalAndNoGlobals) {
-  FieldTrials f0("SomeString/Enabled/");
-  auto f1 = FieldTrials::CreateNoGlobal("SomeOtherString/Enabled/");
-  ASSERT_TRUE(f1);
+TEST(FieldTrialsTest, GlobalAndNonGlobalFieldTrialsAreDisjoint) {
+  FieldTrials f1("SomeString/Enabled/");
+  std::unique_ptr<FieldTrials> f2 =
+      FieldTrials::CreateNoGlobal("SomeOtherString/Enabled/");
+  ASSERT_THAT(f2, NotNull());
 
-  EXPECT_TRUE(f0.IsEnabled("SomeString"));
-  EXPECT_FALSE(f0.IsEnabled("SomeOtherString"));
+  EXPECT_TRUE(f1.IsEnabled("SomeString"));
+  EXPECT_FALSE(f1.IsEnabled("SomeOtherString"));
 
-  EXPECT_FALSE(f1->IsEnabled("SomeString"));
-  EXPECT_TRUE(f1->IsEnabled("SomeOtherString"));
+  EXPECT_FALSE(f2->IsEnabled("SomeString"));
+  EXPECT_TRUE(f2->IsEnabled("SomeOtherString"));
 }
 
+TEST(FieldTrialsTest, FieldTrialBasedConfigReadsGlobalString) {
+  static constexpr char s[] = "MyCoolTrial/Enabled/MyUncoolTrial/Disabled/";
+  webrtc::field_trial::InitFieldTrialsFromString(s);
+  FieldTrialBasedConfig f;
+  EXPECT_TRUE(f.IsEnabled("MyCoolTrial"));
+  EXPECT_TRUE(f.IsDisabled("MyUncoolTrial"));
+}
+
+}  // namespace
 }  // namespace webrtc