diff --git a/client/capture_context_mac_test.cc b/client/capture_context_mac_test.cc
index 53d08e26..3dc0ba8d 100644
--- a/client/capture_context_mac_test.cc
+++ b/client/capture_context_mac_test.cc
@@ -22,10 +22,10 @@
 #include "build/build_config.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 // If the context structure has fields that tell whether it’s valid, such as
 // magic numbers or size fields, sanity-checks those fields for validity with
 // fatal gtest assertions. For other fields, where it’s possible to reason about
@@ -152,3 +152,5 @@ TEST(CaptureContextMac, CaptureContext) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/client/simple_string_dictionary_test.cc b/client/simple_string_dictionary_test.cc
index df963ca5..a55b5a31 100644
--- a/client/simple_string_dictionary_test.cc
+++ b/client/simple_string_dictionary_test.cc
@@ -17,10 +17,10 @@
 #include "base/logging.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(SimpleStringDictionary, Entry) {
   typedef TSimpleStringDictionary<5, 9, 15> TestMap;
   TestMap map;
@@ -293,3 +293,5 @@ TEST(SimpleStringDictionaryDeathTest, NullKey) {
 #endif
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/minidump/minidump_file_writer_test.cc b/minidump/minidump_file_writer_test.cc
index 0ccc0f8e..611dce82 100644
--- a/minidump/minidump_file_writer_test.cc
+++ b/minidump/minidump_file_writer_test.cc
@@ -26,11 +26,10 @@
 #include "util/file/file_writer.h"
 #include "util/file/string_file_writer.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 TEST(MinidumpFileWriter, Empty) {
   MinidumpFileWriter minidump_file;
   StringFileWriter file_writer;
@@ -262,3 +261,5 @@ TEST(MinidumpFileWriterDeathTest, SameStreamType) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/minidump/minidump_memory_writer_test.cc b/minidump/minidump_memory_writer_test.cc
index 3e469874..d81107db 100644
--- a/minidump/minidump_memory_writer_test.cc
+++ b/minidump/minidump_memory_writer_test.cc
@@ -25,11 +25,10 @@
 #include "minidump/minidump_test_util.h"
 #include "util/file/string_file_writer.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 const MinidumpStreamType kBogusStreamType =
     static_cast<MinidumpStreamType>(1234);
 
@@ -389,3 +388,5 @@ TEST(MinidumpMemoryWriter, ExtraMemory) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/minidump/minidump_misc_info_writer_test.cc b/minidump/minidump_misc_info_writer_test.cc
index ca22b592..ea22b59e 100644
--- a/minidump/minidump_misc_info_writer_test.cc
+++ b/minidump/minidump_misc_info_writer_test.cc
@@ -28,11 +28,10 @@
 #include "util/file/string_file_writer.h"
 #include "util/stdlib/strlcpy.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 template <typename T>
 void GetMiscInfoStream(const std::string& file_contents, const T** misc_info) {
   const size_t kDirectoryOffset = sizeof(MINIDUMP_HEADER);
@@ -656,3 +655,5 @@ TEST(MinidumpMiscInfoWriter, Everything) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/minidump/minidump_module_writer_test.cc b/minidump/minidump_module_writer_test.cc
index 296de793..53bf9d78 100644
--- a/minidump/minidump_module_writer_test.cc
+++ b/minidump/minidump_module_writer_test.cc
@@ -26,11 +26,10 @@
 #include "util/file/string_file_writer.h"
 #include "util/misc/uuid.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 void GetModuleListStream(const std::string& file_contents,
                          const MINIDUMP_MODULE_LIST** module_list) {
   const size_t kDirectoryOffset = sizeof(MINIDUMP_HEADER);
@@ -672,3 +671,5 @@ TEST(MinidumpSystemInfoWriterDeathTest, NoModuleName) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/minidump/minidump_string_writer_test.cc b/minidump/minidump_string_writer_test.cc
index 682da831..9e684cef 100644
--- a/minidump/minidump_string_writer_test.cc
+++ b/minidump/minidump_string_writer_test.cc
@@ -24,10 +24,10 @@
 #include "gtest/gtest.h"
 #include "util/file/string_file_writer.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 const MINIDUMP_STRING* MinidumpStringCast(const StringFileWriter& file_writer) {
   return reinterpret_cast<const MINIDUMP_STRING*>(&file_writer.string()[0]);
 }
@@ -199,3 +199,5 @@ TEST(MinidumpStringWriter, MinidumpUTF8StringWriter) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/minidump/minidump_system_info_writer_test.cc b/minidump/minidump_system_info_writer_test.cc
index 98b95d68..48fd9d26 100644
--- a/minidump/minidump_system_info_writer_test.cc
+++ b/minidump/minidump_system_info_writer_test.cc
@@ -24,11 +24,10 @@
 #include "minidump/minidump_test_util.h"
 #include "util/file/string_file_writer.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 void GetSystemInfoStream(const std::string& file_contents,
                          size_t csd_version_length,
                          const MINIDUMP_SYSTEM_INFO** system_info,
@@ -295,3 +294,5 @@ TEST(MinidumpSystemInfoWriterDeathTest, NoCSDVersion) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/minidump/minidump_writable_test.cc b/minidump/minidump_writable_test.cc
index fb52334d..6e345afe 100644
--- a/minidump/minidump_writable_test.cc
+++ b/minidump/minidump_writable_test.cc
@@ -21,10 +21,10 @@
 #include "gtest/gtest.h"
 #include "util/file/string_file_writer.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 class BaseTestMinidumpWritable : public crashpad::internal::MinidumpWritable {
  public:
   BaseTestMinidumpWritable()
@@ -833,3 +833,5 @@ TEST(MinidumpWritable, LocationDescriptor) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/snapshot/cpu_context_mac_test.cc b/snapshot/cpu_context_mac_test.cc
index 16aab4a6..a214a31e 100644
--- a/snapshot/cpu_context_mac_test.cc
+++ b/snapshot/cpu_context_mac_test.cc
@@ -18,10 +18,10 @@
 
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 #if defined(ARCH_CPU_X86_FAMILY)
 
 TEST(CPUContextMac, InitializeContextX86) {
@@ -417,3 +417,5 @@ TEST(CPUContextMac, InitializeContextX86_64) {
 #endif
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/snapshot/system_snapshot_mac_test.cc b/snapshot/system_snapshot_mac_test.cc
index 1f9d1017..bce1137d 100644
--- a/snapshot/system_snapshot_mac_test.cc
+++ b/snapshot/system_snapshot_mac_test.cc
@@ -25,11 +25,10 @@
 #include "util/mac/process_reader.h"
 #include "util/test/errors.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 // SystemSnapshotMac objects would be cumbersome to construct in each test that
 // requires one, because of the repetitive and mechanical work necessary to set
 // up a ProcessReader and timeval, along with the checks to verify that these
@@ -173,3 +172,5 @@ TEST_F(SystemSnapshotMacTest, TimeZone) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/file/string_file_writer_test.cc b/util/file/string_file_writer_test.cc
index b55c778e..d6ea2e49 100644
--- a/util/file/string_file_writer_test.cc
+++ b/util/file/string_file_writer_test.cc
@@ -19,10 +19,10 @@
 
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(StringFileWriter, EmptyFile) {
   StringFileWriter writer;
   EXPECT_TRUE(writer.string().empty());
@@ -376,3 +376,5 @@ TEST(StringFileWriter, SeekInvalid) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mac/checked_mach_address_range_test.cc b/util/mac/checked_mach_address_range_test.cc
index 392121dc..b0f36c3d 100644
--- a/util/mac/checked_mach_address_range_test.cc
+++ b/util/mac/checked_mach_address_range_test.cc
@@ -24,10 +24,10 @@
 #include "gtest/gtest.h"
 #include "util/mac/process_reader.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 #if defined(ARCH_CPU_64_BITS)
 const bool kValid64Invalid32 = true;
 #else
@@ -254,3 +254,5 @@ TEST(CheckedMachAddressRange, ContainsRange) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mac/launchd_test.mm b/util/mac/launchd_test.mm
index b4c8f34a..03953cdf 100644
--- a/util/mac/launchd_test.mm
+++ b/util/mac/launchd_test.mm
@@ -26,10 +26,10 @@
 #include "gtest/gtest.h"
 #include "util/stdlib/objc.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(Launchd, CFPropertyToLaunchData_Integer) {
   @autoreleasepool {
     base::mac::ScopedLaunchData launch_data;
@@ -301,3 +301,5 @@ TEST(Launchd, CFPropertyToLaunchData_RealWorldJobDictionary) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mac/mac_util_test.mm b/util/mac/mac_util_test.mm
index 5c1366fb..7bbba484 100644
--- a/util/mac/mac_util_test.mm
+++ b/util/mac/mac_util_test.mm
@@ -34,10 +34,10 @@
 #undef catch
 #endif
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 // Runs /usr/bin/sw_vers with a single argument, |argument|, and places the
 // command’s standard output into |output| after stripping the trailing newline.
 // Fatal gtest assertions report tool failures, which the caller should check
@@ -147,3 +147,5 @@ TEST(MacUtil, MacModelAndBoard) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mac/mach_o_image_reader_test.cc b/util/mac/mach_o_image_reader_test.cc
index 2991cc5f..f174a4ea 100644
--- a/util/mac/mach_o_image_reader_test.cc
+++ b/util/mac/mach_o_image_reader_test.cc
@@ -36,10 +36,10 @@
 // This file is responsible for testing MachOImageReader,
 // MachOImageSegmentReader, and MachOImageSymbolTableReader.
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 // Native types and constants, in cases where the 32-bit and 64-bit versions
 // are different.
 #if defined(ARCH_CPU_64_BITS)
@@ -659,3 +659,5 @@ TEST(MachOImageReader, Self_DyldImages) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mac/mach_o_image_segment_reader_test.cc b/util/mac/mach_o_image_segment_reader_test.cc
index 226eaa07..d0e706f8 100644
--- a/util/mac/mach_o_image_segment_reader_test.cc
+++ b/util/mac/mach_o_image_segment_reader_test.cc
@@ -20,10 +20,10 @@
 #include "base/strings/stringprintf.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 // Most of MachOImageSegmentReader is tested as part of MachOImageReader, which
 // depends on MachOImageSegmentReader to provide major portions of its
 // functionality. Because MachOImageSegmentReader is difficult to use except by
@@ -184,3 +184,5 @@ TEST(MachOImageSegmentReader, SegmentAndSectionNameString) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mac/process_reader_test.cc b/util/mac/process_reader_test.cc
index 795468f5..e67c98e8 100644
--- a/util/mac/process_reader_test.cc
+++ b/util/mac/process_reader_test.cc
@@ -40,11 +40,10 @@
 #include "util/test/mac/mach_errors.h"
 #include "util/test/mac/mach_multiprocess.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 TEST(ProcessReader, SelfBasic) {
   ProcessReader process_reader;
   ASSERT_TRUE(process_reader.Initialize(mach_task_self()));
@@ -695,3 +694,5 @@ TEST(ProcessReader, ChildModules) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mac/process_types_test.cc b/util/mac/process_types_test.cc
index 80abe751..93ecc2aa 100644
--- a/util/mac/process_types_test.cc
+++ b/util/mac/process_types_test.cc
@@ -25,10 +25,10 @@
 #include "util/mac/mac_util.h"
 #include "util/test/mac/dyld.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 #define TEST_STRING(process_reader, self_view, proctype_view, field)        \
   do {                                                                      \
     if (self_view->field) {                                                 \
@@ -259,3 +259,5 @@ TEST(ProcessTypes, DyldImagesSelf) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mac/service_management_test.mm b/util/mac/service_management_test.mm
index 9ca2e15a..27827216 100644
--- a/util/mac/service_management_test.mm
+++ b/util/mac/service_management_test.mm
@@ -30,10 +30,10 @@
 #include "util/posix/process_util.h"
 #include "util/stdlib/objc.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 // Ensures that the process with the specified PID is running, identifying it by
 // requiring that its argv[argc - 1] compare equal to last_arg.
 void ExpectProcessIsRunning(pid_t pid, std::string& last_arg) {
@@ -156,3 +156,5 @@ TEST(ServiceManagement, SubmitRemoveJob) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mach/exc_client_variants_test.cc b/util/mach/exc_client_variants_test.cc
index 3f292690..0070880a 100644
--- a/util/mach/exc_client_variants_test.cc
+++ b/util/mach/exc_client_variants_test.cc
@@ -27,11 +27,10 @@
 #include "util/test/mac/mach_errors.h"
 #include "util/test/mac/mach_multiprocess.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 class TestExcClientVariants : public UniversalMachExcServer,
                               public MachMultiprocess {
  public:
@@ -287,3 +286,5 @@ TEST(ExcClientVariants, UniversalExceptionRaise) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mach/exc_server_variants_test.cc b/util/mach/exc_server_variants_test.cc
index 5daa81ba..eea6dce6 100644
--- a/util/mach/exc_server_variants_test.cc
+++ b/util/mach/exc_server_variants_test.cc
@@ -27,11 +27,14 @@
 #include "util/test/mac/mach_errors.h"
 #include "util/test/mac/mach_multiprocess.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-using namespace testing;
+using testing::DefaultValue;
+using testing::Eq;
+using testing::Pointee;
+using testing::Return;
 
 // Fake Mach ports. These aren’t used as ports in these tests, they’re just used
 // as cookies to make sure that the correct values get passed to the correct
@@ -1169,3 +1172,5 @@ TEST(ExcServerVariants, ExcServerSuccessfulReturnValue) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mach/exception_behaviors_test.cc b/util/mach/exception_behaviors_test.cc
index c4497d61..cbde600a 100644
--- a/util/mach/exception_behaviors_test.cc
+++ b/util/mach/exception_behaviors_test.cc
@@ -19,10 +19,10 @@
 #include "gtest/gtest.h"
 #include "util/mach/mach_extensions.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(ExceptionBehaviors, ExceptionBehaviors) {
   struct TestData {
     exception_behavior_t behavior;
@@ -68,3 +68,5 @@ TEST(ExceptionBehaviors, ExceptionBehaviors) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mach/exception_ports_test.cc b/util/mach/exception_ports_test.cc
index a5424a58..56cda3c2 100644
--- a/util/mach/exception_ports_test.cc
+++ b/util/mach/exception_ports_test.cc
@@ -33,11 +33,10 @@
 #include "util/test/mac/mach_errors.h"
 #include "util/test/mac/mach_multiprocess.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 // Calls GetExceptionPorts() on its |exception_ports| argument to look up the
 // EXC_MASK_CRASH handler. If |expect_port| is not MACH_PORT_NULL, it expects to
 // find a handler for this mask whose port matches |expect_port| and whose
@@ -574,3 +573,5 @@ TEST(ExceptionPorts, HostExceptionPorts) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mach/mach_extensions_test.cc b/util/mach/mach_extensions_test.cc
index 511c8900..9334d30a 100644
--- a/util/mach/mach_extensions_test.cc
+++ b/util/mach/mach_extensions_test.cc
@@ -17,13 +17,15 @@
 #include "base/mac/scoped_mach_port.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(MachExtensions, MachThreadSelf) {
   base::mac::ScopedMachSendRight thread_self(mach_thread_self());
   EXPECT_EQ(thread_self, MachThreadSelf());
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mach/mach_message_server_test.cc b/util/mach/mach_message_server_test.cc
index 3d0d8bd7..f732bbc2 100644
--- a/util/mach/mach_message_server_test.cc
+++ b/util/mach/mach_message_server_test.cc
@@ -25,11 +25,10 @@
 #include "util/test/mac/mach_errors.h"
 #include "util/test/mac/mach_multiprocess.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 class TestMachMessageServer : public MachMessageServer::Interface,
                               public MachMultiprocess {
  public:
@@ -845,3 +844,5 @@ TEST(MachMessageServer, LargeExpected) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mach/symbolic_constants_mach_test.cc b/util/mach/symbolic_constants_mach_test.cc
index 4bc17c81..0410f2e3 100644
--- a/util/mach/symbolic_constants_mach_test.cc
+++ b/util/mach/symbolic_constants_mach_test.cc
@@ -25,10 +25,10 @@
 
 #define NUL_TEST_DATA(string) { string, arraysize(string) - 1 }
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 // Options to use for normal tests, those that don’t require kAllowOr.
 const StringToSymbolicConstantOptions kNormalOptions[] = {
     0,
@@ -1062,3 +1062,5 @@ TEST(SymbolicConstantsMach, StringToThreadStateFlavor) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/mach/task_memory_test.cc b/util/mach/task_memory_test.cc
index 3ee813ab..523e95a5 100644
--- a/util/mach/task_memory_test.cc
+++ b/util/mach/task_memory_test.cc
@@ -26,11 +26,10 @@
 #include "gtest/gtest.h"
 #include "util/test/mac/mach_errors.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 TEST(TaskMemory, ReadSelf) {
   vm_address_t address = 0;
   const vm_size_t kSize = 4 * PAGE_SIZE;
@@ -552,3 +551,5 @@ TEST(TaskMemory, MappedMemoryReadCString) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/misc/clock_test.cc b/util/misc/clock_test.cc
index 35ec1ac1..8082e951 100644
--- a/util/misc/clock_test.cc
+++ b/util/misc/clock_test.cc
@@ -23,10 +23,10 @@
 #include "base/strings/stringprintf.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(Clock, ClockMonotonicNanoseconds) {
   uint64_t start = ClockMonotonicNanoseconds();
   EXPECT_GT(start, 0u);
@@ -92,3 +92,5 @@ TEST(Clock, SleepNanoseconds) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/misc/initialization_state_dcheck_test.cc b/util/misc/initialization_state_dcheck_test.cc
index 57a4e54a..c9b595ac 100644
--- a/util/misc/initialization_state_dcheck_test.cc
+++ b/util/misc/initialization_state_dcheck_test.cc
@@ -17,10 +17,10 @@
 #include "base/logging.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(InitializationStateDcheck, InitializationStateDcheck) {
   InitializationStateDcheck initialization_state_dcheck;
   INITIALIZATION_STATE_SET_INITIALIZING(initialization_state_dcheck);
@@ -126,3 +126,5 @@ TEST(InitializationStateDcheckDeathTest, Destroyed_NotValid) {
 #endif
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/misc/initialization_state_test.cc b/util/misc/initialization_state_test.cc
index 8330f301..d427a140 100644
--- a/util/misc/initialization_state_test.cc
+++ b/util/misc/initialization_state_test.cc
@@ -16,10 +16,10 @@
 
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(InitializationState, InitializationState) {
   InitializationState* initialization_state_pointer;
   {
@@ -54,3 +54,5 @@ TEST(InitializationState, InitializationState) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/misc/scoped_forbid_return_test.cc b/util/misc/scoped_forbid_return_test.cc
index 0349fc15..9a1b6d90 100644
--- a/util/misc/scoped_forbid_return_test.cc
+++ b/util/misc/scoped_forbid_return_test.cc
@@ -16,10 +16,10 @@
 
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 enum ForbidReturnType {
   kForbidReturnDefault = 0,
   kForbidReturnArmed,
@@ -57,3 +57,5 @@ TEST(ScopedForbidReturn, Disarmed) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/misc/uuid_test.cc b/util/misc/uuid_test.cc
index 5d515cc6..2bd4ceb0 100644
--- a/util/misc/uuid_test.cc
+++ b/util/misc/uuid_test.cc
@@ -21,10 +21,10 @@
 #include "base/basictypes.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(UUID, UUID) {
   UUID uuid_zero;
   EXPECT_EQ(0u, uuid_zero.data_1);
@@ -153,3 +153,5 @@ TEST(UUID, UUID) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/numeric/checked_range_test.cc b/util/numeric/checked_range_test.cc
index baa843a5..37d482c7 100644
--- a/util/numeric/checked_range_test.cc
+++ b/util/numeric/checked_range_test.cc
@@ -22,10 +22,10 @@
 #include "base/strings/stringprintf.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(CheckedRange, IsValid) {
   const struct UnsignedTestData {
     uint32_t base;
@@ -244,3 +244,5 @@ TEST(CheckedRange, ContainsRange) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/numeric/in_range_cast_test.cc b/util/numeric/in_range_cast_test.cc
index 340c862c..52eeedf5 100644
--- a/util/numeric/in_range_cast_test.cc
+++ b/util/numeric/in_range_cast_test.cc
@@ -20,10 +20,10 @@
 
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 const int32_t kInt32Min = std::numeric_limits<int32_t>::min();
 const int64_t kInt64Min = std::numeric_limits<int64_t>::min();
 
@@ -115,3 +115,5 @@ TEST(InRangeCast, Int64) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/numeric/int128_test.cc b/util/numeric/int128_test.cc
index 0fbf2c22..e2f02a43 100644
--- a/util/numeric/int128_test.cc
+++ b/util/numeric/int128_test.cc
@@ -17,10 +17,10 @@
 #include "base/basictypes.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(Int128, UInt128) {
 #if defined(ARCH_CPU_LITTLE_ENDIAN)
   const uint8_t kBytes[] =
@@ -40,3 +40,5 @@ TEST(Int128, UInt128) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/posix/process_util_test.cc b/util/posix/process_util_test.cc
index 2fb6841e..47b0dd5f 100644
--- a/util/posix/process_util_test.cc
+++ b/util/posix/process_util_test.cc
@@ -22,10 +22,10 @@
 
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(ProcessUtil, ProcessArgumentsForPID) {
   std::vector<std::string> argv;
   ASSERT_TRUE(ProcessArgumentsForPID(getpid(), &argv));
@@ -45,3 +45,5 @@ TEST(ProcessUtil, ProcessArgumentsForPID) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/posix/symbolic_constants_posix_test.cc b/util/posix/symbolic_constants_posix_test.cc
index a03e8beb..c80d00d9 100644
--- a/util/posix/symbolic_constants_posix_test.cc
+++ b/util/posix/symbolic_constants_posix_test.cc
@@ -23,10 +23,10 @@
 
 #define NUL_TEST_DATA(string) { string, arraysize(string) - 1 }
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 const struct {
   int signal;
   const char* full_name;
@@ -252,3 +252,5 @@ TEST(SymbolicConstantsPOSIX, StringToSignal) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/stdlib/string_number_conversion_test.cc b/util/stdlib/string_number_conversion_test.cc
index ef1376c7..ec0d44ae 100644
--- a/util/stdlib/string_number_conversion_test.cc
+++ b/util/stdlib/string_number_conversion_test.cc
@@ -19,10 +19,10 @@
 
 #include <limits>
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(StringNumberConversion, StringToInt) {
   const struct {
     const char* string;
@@ -216,3 +216,5 @@ TEST(StringNumberConversion, StringToUnsignedInt) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/stdlib/strlcpy_test.cc b/util/stdlib/strlcpy_test.cc
index 1cf187c2..8eb656da 100644
--- a/util/stdlib/strlcpy_test.cc
+++ b/util/stdlib/strlcpy_test.cc
@@ -23,10 +23,10 @@
 #include "base/strings/stringprintf.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(strlcpy, c16lcpy) {
   // Use a destination buffer that’s larger than the length passed to c16lcpy.
   // The unused portion is a guard area that must not be written to.
@@ -89,3 +89,5 @@ TEST(strlcpy, c16lcpy) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/stdlib/strnlen_test.cc b/util/stdlib/strnlen_test.cc
index f5b6845b..35ca7f1a 100644
--- a/util/stdlib/strnlen_test.cc
+++ b/util/stdlib/strnlen_test.cc
@@ -18,6 +18,8 @@
 
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
 TEST(strnlen, strnlen) {
@@ -39,3 +41,5 @@ TEST(strnlen, strnlen) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/synchronization/semaphore_test.cc b/util/synchronization/semaphore_test.cc
index 3eb53da7..07cc45b7 100644
--- a/util/synchronization/semaphore_test.cc
+++ b/util/synchronization/semaphore_test.cc
@@ -18,10 +18,10 @@
 
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-
 TEST(Semaphore, Simple) {
   Semaphore semaphore(1);
   semaphore.Wait();
@@ -86,3 +86,5 @@ TEST(Semaphore, TenThreaded) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/test/executable_path_test.cc b/util/test/executable_path_test.cc
index b99d3d91..3682a4b3 100644
--- a/util/test/executable_path_test.cc
+++ b/util/test/executable_path_test.cc
@@ -17,10 +17,10 @@
 #include "base/files/file_path.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad::test;
-
 TEST(ExecutablePath, ExecutablePath) {
   base::FilePath executable_path = ExecutablePath();
   base::FilePath executable_name = executable_path.BaseName();
@@ -28,3 +28,5 @@ TEST(ExecutablePath, ExecutablePath) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/test/mac/mach_multiprocess.cc b/util/test/mac/mach_multiprocess.cc
index f8603afa..568e3147 100644
--- a/util/test/mac/mach_multiprocess.cc
+++ b/util/test/mac/mach_multiprocess.cc
@@ -48,8 +48,6 @@ struct ReceiveHelloMessage : public SendHelloMessage {
 namespace crashpad {
 namespace test {
 
-using namespace testing;
-
 namespace internal {
 
 struct MachMultiprocessInfo {
@@ -271,7 +269,7 @@ void MachMultiprocess::MultiprocessChild() {
   // verify it using the task port it has access to via ChildTask().
   CheckedReadFDAtEOF(ReadPipeFD());
 
-  if (Test::HasFailure()) {
+  if (testing::Test::HasFailure()) {
     // Trigger the ScopedForbidReturn destructor.
     return;
   }
diff --git a/util/test/mac/mach_multiprocess_test.cc b/util/test/mac/mach_multiprocess_test.cc
index 39295f65..388831fd 100644
--- a/util/test/mac/mach_multiprocess_test.cc
+++ b/util/test/mac/mach_multiprocess_test.cc
@@ -19,11 +19,10 @@
 #include "base/basictypes.h"
 #include "gtest/gtest.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 class TestMachMultiprocess final : public MachMultiprocess {
  public:
   TestMachMultiprocess() : MachMultiprocess() {}
@@ -46,3 +45,5 @@ TEST(MachMultiprocess, MachMultiprocess) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/test/multiprocess.cc b/util/test/multiprocess.cc
index df8212d4..79568374 100644
--- a/util/test/multiprocess.cc
+++ b/util/test/multiprocess.cc
@@ -33,8 +33,6 @@
 namespace crashpad {
 namespace test {
 
-using namespace testing;
-
 namespace internal {
 
 struct MultiprocessInfo {
@@ -211,7 +209,7 @@ void Multiprocess::RunChild() {
   info_->pipe_c2p_write.reset();
   info_->pipe_p2c_read.reset();
 
-  if (Test::HasFailure()) {
+  if (testing::Test::HasFailure()) {
     // Trigger the ScopedForbidReturn destructor.
     return;
   }
diff --git a/util/test/multiprocess_exec.cc b/util/test/multiprocess_exec.cc
index 4888a809..fdf98eaf 100644
--- a/util/test/multiprocess_exec.cc
+++ b/util/test/multiprocess_exec.cc
@@ -27,8 +27,6 @@
 namespace crashpad {
 namespace test {
 
-using namespace testing;
-
 MultiprocessExec::MultiprocessExec()
     : Multiprocess(),
       command_(),
diff --git a/util/test/multiprocess_exec_test.cc b/util/test/multiprocess_exec_test.cc
index 2f30b9b0..d70f0d06 100644
--- a/util/test/multiprocess_exec_test.cc
+++ b/util/test/multiprocess_exec_test.cc
@@ -21,11 +21,10 @@
 #include "util/file/fd_io.h"
 #include "util/test/executable_path.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 class TestMultiprocessExec final : public MultiprocessExec {
  public:
   TestMultiprocessExec() : MultiprocessExec() {}
@@ -54,3 +53,5 @@ TEST(MultiprocessExec, MultiprocessExec) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad
diff --git a/util/test/multiprocess_test.cc b/util/test/multiprocess_test.cc
index b1a96856..ec4394e0 100644
--- a/util/test/multiprocess_test.cc
+++ b/util/test/multiprocess_test.cc
@@ -22,11 +22,10 @@
 #include "gtest/gtest.h"
 #include "util/file/fd_io.h"
 
+namespace crashpad {
+namespace test {
 namespace {
 
-using namespace crashpad;
-using namespace crashpad::test;
-
 class TestMultiprocess final : public Multiprocess {
  public:
   TestMultiprocess() : Multiprocess() {}
@@ -292,3 +291,5 @@ TEST(MultiprocessDeathTest, ChildClosesReadAndWritePipe) {
 }
 
 }  // namespace
+}  // namespace test
+}  // namespace crashpad