diff --git a/mojo/edk/embedder/embedder.h b/mojo/edk/embedder/embedder.h
index 50ec184..2e43475 100644
--- a/mojo/edk/embedder/embedder.h
+++ b/mojo/edk/embedder/embedder.h
@@ -23,7 +23,7 @@
 struct Configuration;
 class PlatformSupport;
 class ProcessDelegate;
-typedef void* SlaveInfo;
+using SlaveInfo = void*;
 
 // Basic configuration/initialization ------------------------------------------
 
@@ -191,7 +191,7 @@
 CreateChannelOnIOThread(ScopedPlatformHandle platform_handle,
                         ChannelInfo** channel_info);
 
-typedef base::Callback<void(ChannelInfo*)> DidCreateChannelCallback;
+using DidCreateChannelCallback = base::Callback<void(ChannelInfo*)>;
 // Creates a channel asynchronously; may be called from any thread.
 // |platform_handle| should be a handle to a connected OS "pipe".
 // |io_thread_task_runner| should be the |TaskRunner| for the I/O thread.
@@ -214,7 +214,7 @@
 MOJO_SYSTEM_IMPL_EXPORT void DestroyChannelOnIOThread(
     ChannelInfo* channel_info);
 
-typedef base::Closure DidDestroyChannelCallback;
+using DidDestroyChannelCallback = base::Closure;
 // Like |DestroyChannelOnIOThread()|, but asynchronous and may be called from
 // any thread. The callback will be called using |callback_thread_task_runner|
 // if that is non-null, or otherwise it will be called on the "channel thread".
diff --git a/mojo/edk/embedder/embedder_internal.h b/mojo/edk/embedder/embedder_internal.h
index 833e66b..752d366 100644
--- a/mojo/edk/embedder/embedder_internal.h
+++ b/mojo/edk/embedder/embedder_internal.h
@@ -24,8 +24,8 @@
 class ChannelManager;
 class Core;
 
-// Repeat a typedef in mojo/edk/system/channel_manager.h, to avoid including it.
-typedef uint64_t ChannelId;
+// Duplicate from mojo/edk/system/channel_manager.h, to avoid including it.
+using ChannelId = uint64_t;
 
 }  // namespace system
 
diff --git a/mojo/edk/embedder/master_process_delegate.h b/mojo/edk/embedder/master_process_delegate.h
index bc3c909..22ac435 100644
--- a/mojo/edk/embedder/master_process_delegate.h
+++ b/mojo/edk/embedder/master_process_delegate.h
@@ -13,7 +13,7 @@
 namespace mojo {
 namespace embedder {
 
-typedef void* SlaveInfo;
+using SlaveInfo = void*;
 
 // An interface for the master process delegate (which lives in the master
 // process).
diff --git a/mojo/edk/embedder/platform_channel_pair.h b/mojo/edk/embedder/platform_channel_pair.h
index d77c100..ff8aabd 100644
--- a/mojo/edk/embedder/platform_channel_pair.h
+++ b/mojo/edk/embedder/platform_channel_pair.h
@@ -22,9 +22,9 @@
 // It would be nice to refactor base/process/launch.h to have a more platform-
 // independent way of representing handles that are passed to child processes.
 #if defined(OS_WIN)
-typedef base::HandlesToInheritVector HandlePassingInformation;
+using HandlePassingInformation = base::HandlesToInheritVector;
 #elif defined(OS_POSIX)
-typedef base::FileHandleMappingVector HandlePassingInformation;
+using HandlePassingInformation = base::FileHandleMappingVector;
 #else
 #error "Unsupported."
 #endif
diff --git a/mojo/edk/embedder/platform_handle_vector.h b/mojo/edk/embedder/platform_handle_vector.h
index 96356b7..771df4f 100644
--- a/mojo/edk/embedder/platform_handle_vector.h
+++ b/mojo/edk/embedder/platform_handle_vector.h
@@ -15,7 +15,7 @@
 namespace mojo {
 namespace embedder {
 
-typedef std::vector<PlatformHandle> PlatformHandleVector;
+using PlatformHandleVector = std::vector<PlatformHandle>;
 
 // A deleter (for use with |scoped_ptr|) which closes all handles and then
 // |delete|s the |PlatformHandleVector|.
@@ -26,8 +26,8 @@
   }
 };
 
-typedef scoped_ptr<PlatformHandleVector, PlatformHandleVectorDeleter>
-    ScopedPlatformHandleVectorPtr;
+using ScopedPlatformHandleVectorPtr =
+    scoped_ptr<PlatformHandleVector, PlatformHandleVectorDeleter>;
 
 }  // namespace embedder
 }  // namespace mojo
diff --git a/mojo/edk/js/drain_data.h b/mojo/edk/js/drain_data.h
index 48f1de2..3c066dc 100644
--- a/mojo/edk/js/drain_data.h
+++ b/mojo/edk/js/drain_data.h
@@ -48,7 +48,7 @@
   // all of the buffered data to the JS Promise and then delete this.
   void DeliverData(MojoResult result);
 
-  typedef std::vector<char> DataBuffer;
+  using DataBuffer = std::vector<char>;
 
   v8::Isolate* isolate_;
   ScopedDataPipeConsumerHandle handle_;
diff --git a/mojo/edk/system/async_waiter.h b/mojo/edk/system/async_waiter.h
index df3b482..be228e5 100644
--- a/mojo/edk/system/async_waiter.h
+++ b/mojo/edk/system/async_waiter.h
@@ -17,7 +17,7 @@
 // An |Awakable| implementation that just calls a given callback object.
 class MOJO_SYSTEM_IMPL_EXPORT AsyncWaiter final : public Awakable {
  public:
-  typedef base::Callback<void(MojoResult)> AwakeCallback;
+  using AwakeCallback = base::Callback<void(MojoResult)>;
 
   // |callback| must satisfy the same contract as |Awakable::Awake()|.
   explicit AsyncWaiter(const AwakeCallback& callback);
diff --git a/mojo/edk/system/awakable_list.h b/mojo/edk/system/awakable_list.h
index 19c03c8..2d8101e 100644
--- a/mojo/edk/system/awakable_list.h
+++ b/mojo/edk/system/awakable_list.h
@@ -45,7 +45,7 @@
     MojoHandleSignals signals;
     uint32_t context;
   };
-  typedef std::list<AwakeInfo> AwakeInfoList;
+  using AwakeInfoList = std::list<AwakeInfo>;
 
   AwakeInfoList awakables_;
 
diff --git a/mojo/edk/system/channel.h b/mojo/edk/system/channel.h
index 93ba87a..a22d506 100644
--- a/mojo/edk/system/channel.h
+++ b/mojo/edk/system/channel.h
@@ -235,16 +235,16 @@
   // Has a reference to us.
   ChannelManager* channel_manager_;
 
-  typedef base::hash_map<ChannelEndpointId, scoped_refptr<ChannelEndpoint>>
-      IdToEndpointMap;
+  using IdToEndpointMap =
+      base::hash_map<ChannelEndpointId, scoped_refptr<ChannelEndpoint>>;
   // Map from local IDs to endpoints. If the endpoint is null, this means that
   // we're just waiting for the remove ack before removing the entry.
   IdToEndpointMap local_id_to_endpoint_map_;
   // Note: The IDs generated by this should be checked for existence before use.
   LocalChannelEndpointIdGenerator local_id_generator_;
 
-  typedef base::hash_map<ChannelEndpointId, scoped_refptr<IncomingEndpoint>>
-      IdToIncomingEndpointMap;
+  using IdToIncomingEndpointMap =
+      base::hash_map<ChannelEndpointId, scoped_refptr<IncomingEndpoint>>;
   // Map from local IDs to incoming endpoints (i.e., those received inside other
   // messages, but not yet claimed via |DeserializeEndpoint()|).
   IdToIncomingEndpointMap incoming_endpoints_;
diff --git a/mojo/edk/system/channel_manager.h b/mojo/edk/system/channel_manager.h
index 77ff953..19c3b42 100644
--- a/mojo/edk/system/channel_manager.h
+++ b/mojo/edk/system/channel_manager.h
@@ -34,7 +34,7 @@
 
 // IDs for |Channel|s managed by a |ChannelManager|. (IDs should be thought of
 // as specific to a given |ChannelManager|.) 0 is never a valid ID.
-typedef uint64_t ChannelId;
+using ChannelId = uint64_t;
 
 const ChannelId kInvalidChannelId = 0;
 
diff --git a/mojo/edk/system/connection_manager.h b/mojo/edk/system/connection_manager.h
index 8820dd5..bc2769f 100644
--- a/mojo/edk/system/connection_manager.h
+++ b/mojo/edk/system/connection_manager.h
@@ -20,10 +20,10 @@
 
 // (Temporary, unique) identifiers for connections, used as they are being
 // brought up:
-typedef UniqueIdentifier ConnectionIdentifier;
+using ConnectionIdentifier = UniqueIdentifier;
 
 // Identifiers for processes (note that these are not OS process IDs):
-typedef uint64_t ProcessIdentifier;
+using ProcessIdentifier = uint64_t;
 const ProcessIdentifier kInvalidProcessIdentifier = 0;
 
 // |ConnectionManager| is an interface for the system that allows "connections"
diff --git a/mojo/edk/system/core_test_base.h b/mojo/edk/system/core_test_base.h
index 26b7925..3eb2364 100644
--- a/mojo/edk/system/core_test_base.h
+++ b/mojo/edk/system/core_test_base.h
@@ -23,7 +23,7 @@
 
 class CoreTestBase : public testing::Test {
  public:
-  typedef CoreTestBase_MockHandleInfo MockHandleInfo;
+  using MockHandleInfo = CoreTestBase_MockHandleInfo;
 
   CoreTestBase();
   ~CoreTestBase() override;
diff --git a/mojo/edk/system/core_unittest.cc b/mojo/edk/system/core_unittest.cc
index b789301..c562097 100644
--- a/mojo/edk/system/core_unittest.cc
+++ b/mojo/edk/system/core_unittest.cc
@@ -24,7 +24,7 @@
                                       MOJO_HANDLE_SIGNAL_WRITABLE |
                                       MOJO_HANDLE_SIGNAL_PEER_CLOSED;
 
-typedef test::CoreTestBase CoreTest;
+using CoreTest = test::CoreTestBase;
 
 TEST_F(CoreTest, GetTimeTicksNow) {
   const MojoTimeTicks start = core()->GetTimeTicksNow();
diff --git a/mojo/edk/system/data_pipe_impl_unittest.cc b/mojo/edk/system/data_pipe_impl_unittest.cc
index 17021f3..3a77488 100644
--- a/mojo/edk/system/data_pipe_impl_unittest.cc
+++ b/mojo/edk/system/data_pipe_impl_unittest.cc
@@ -549,11 +549,11 @@
 
 // Test case instantiation -----------------------------------------------------
 
-typedef testing::Types<LocalDataPipeImplTestHelper,
-                       RemoteProducerDataPipeImplTestHelper,
-                       RemoteConsumerDataPipeImplTestHelper,
-                       RemoteProducerDataPipeImplTestHelper2,
-                       RemoteConsumerDataPipeImplTestHelper2> HelperTypes;
+using HelperTypes = testing::Types<LocalDataPipeImplTestHelper,
+                                   RemoteProducerDataPipeImplTestHelper,
+                                   RemoteConsumerDataPipeImplTestHelper,
+                                   RemoteProducerDataPipeImplTestHelper2,
+                                   RemoteConsumerDataPipeImplTestHelper2>;
 
 TYPED_TEST_CASE(DataPipeImplTest, HelperTypes);
 
diff --git a/mojo/edk/system/dispatcher.h b/mojo/edk/system/dispatcher.h
index 4bbc5ed..8d7e1cb 100644
--- a/mojo/edk/system/dispatcher.h
+++ b/mojo/edk/system/dispatcher.h
@@ -41,7 +41,7 @@
 class TransportData;
 class Awakable;
 
-typedef std::vector<scoped_refptr<Dispatcher>> DispatcherVector;
+using DispatcherVector = std::vector<scoped_refptr<Dispatcher>>;
 
 namespace test {
 
diff --git a/mojo/edk/system/handle_table.h b/mojo/edk/system/handle_table.h
index 9385643..64ad183 100644
--- a/mojo/edk/system/handle_table.h
+++ b/mojo/edk/system/handle_table.h
@@ -21,7 +21,7 @@
 class Dispatcher;
 class DispatcherTransport;
 
-typedef std::vector<scoped_refptr<Dispatcher>> DispatcherVector;
+using DispatcherVector = std::vector<scoped_refptr<Dispatcher>>;
 
 // Test-only function (defined/used in embedder/test_embedder.cc). Declared here
 // so it can be friended.
@@ -126,7 +126,7 @@
     scoped_refptr<Dispatcher> dispatcher;
     bool busy;
   };
-  typedef base::hash_map<MojoHandle, Entry> HandleToEntryMap;
+  using HandleToEntryMap = base::hash_map<MojoHandle, Entry>;
 
   // Adds the given dispatcher to the handle table, not doing any size checks.
   MojoHandle AddDispatcherNoSizeCheck(
diff --git a/mojo/edk/system/mapping_table.h b/mojo/edk/system/mapping_table.h
index d2812d8..ed1732d 100644
--- a/mojo/edk/system/mapping_table.h
+++ b/mojo/edk/system/mapping_table.h
@@ -49,8 +49,8 @@
  private:
   friend bool internal::ShutdownCheckNoLeaks(Core*);
 
-  typedef base::hash_map<uintptr_t, embedder::PlatformSharedBufferMapping*>
-      AddressToMappingMap;
+  using AddressToMappingMap =
+      base::hash_map<uintptr_t, embedder::PlatformSharedBufferMapping*>;
   AddressToMappingMap address_to_mapping_map_;
 
   DISALLOW_COPY_AND_ASSIGN(MappingTable);
diff --git a/mojo/edk/system/master_connection_manager.h b/mojo/edk/system/master_connection_manager.h
index 3210361..d7f06b5 100644
--- a/mojo/edk/system/master_connection_manager.h
+++ b/mojo/edk/system/master_connection_manager.h
@@ -25,7 +25,7 @@
 
 namespace embedder {
 class MasterProcessDelegate;
-typedef void* SlaveInfo;
+using SlaveInfo = void*;
 }
 
 namespace system {
diff --git a/mojo/edk/system/memory.h b/mojo/edk/system/memory.h
index 96cf219..2f1bde4 100644
--- a/mojo/edk/system/memory.h
+++ b/mojo/edk/system/memory.h
@@ -23,25 +23,25 @@
 // TODO(vtl): Remove these once we have the C++11 |remove_const|.
 template <typename T>
 struct remove_const {
-  typedef T type;
+  using type = T;
 };
 template <typename T>
 struct remove_const<const T> {
-  typedef T type;
+  using type = T;
 };
 
 // Yields |(const) char| if |T| is |(const) void|, else |T|:
 template <typename T>
 struct VoidToChar {
-  typedef T type;
+  using type = T;
 };
 template <>
 struct VoidToChar<void> {
-  typedef char type;
+  using type = char;
 };
 template <>
 struct VoidToChar<const void> {
-  typedef const char type;
+  using type = const char;
 };
 
 // Checks (insofar as appropriate/possible) that |pointer| is a valid pointer to
@@ -84,7 +84,7 @@
 template <typename Type>
 class UserPointer {
  private:
-  typedef typename internal::VoidToChar<Type>::type NonVoidType;
+  using NonVoidType = typename internal::VoidToChar<Type>::type;
 
  public:
   // Instead of explicitly using these constructors, you can often use
@@ -243,9 +243,9 @@
   //
   // TODO(vtl): Possibly, since we're not really being safe, we should just not
   // copy for Release builds.
-  typedef UserPointerReader<Type> Reader;
-  typedef UserPointerWriter<Type> Writer;
-  typedef UserPointerReaderWriter<Type> ReaderWriter;
+  using Reader = UserPointerReader<Type>;
+  using Writer = UserPointerWriter<Type>;
+  using ReaderWriter = UserPointerReaderWriter<Type>;
 
  private:
   friend class UserPointerReader<Type>;
@@ -269,7 +269,7 @@
 template <typename Type>
 class UserPointerReader {
  private:
-  typedef typename internal::remove_const<Type>::type TypeNoConst;
+  using TypeNoConst = typename internal::remove_const<Type>::type;
 
  public:
   // Note: If |count| is zero, |GetPointer()| will always return null.
diff --git a/mojo/edk/system/message_in_transit.h b/mojo/edk/system/message_in_transit.h
index 038a292..3ade44b 100644
--- a/mojo/edk/system/message_in_transit.h
+++ b/mojo/edk/system/message_in_transit.h
@@ -43,7 +43,7 @@
 // buffer.
 class MOJO_SYSTEM_IMPL_EXPORT MessageInTransit {
  public:
-  typedef uint16_t Type;
+  using Type = uint16_t;
   // Messages that are forwarded to endpoint clients.
   static const Type kTypeEndpointClient = 0;
   // Messages that are consumed by the |ChannelEndpoint|.
@@ -58,7 +58,7 @@
   // Messages sent by a |MasterConnectionManager| (all responses).
   static const Type kTypeConnectionManagerAck = 5;
 
-  typedef uint16_t Subtype;
+  using Subtype = uint16_t;
   // Subtypes for type |kTypeEndpointClient|:
   // Message pipe or data pipe data (etc.).
   static const Subtype kSubtypeEndpointClientData = 0;
diff --git a/mojo/edk/system/options_validation_unittest.cc b/mojo/edk/system/options_validation_unittest.cc
index 89c4e60..298355c 100644
--- a/mojo/edk/system/options_validation_unittest.cc
+++ b/mojo/edk/system/options_validation_unittest.cc
@@ -16,7 +16,7 @@
 
 // Declare a test options struct just as we do in actual public headers.
 
-typedef uint32_t TestOptionsFlags;
+using TestOptionsFlags = uint32_t;
 
 static_assert(MOJO_ALIGNOF(int64_t) == 8, "int64_t has weird alignment");
 struct MOJO_ALIGNAS(8) TestOptions {
diff --git a/mojo/edk/system/raw_channel_win.cc b/mojo/edk/system/raw_channel_win.cc
index a422c9e..cd9bfdf 100644
--- a/mojo/edk/system/raw_channel_win.cc
+++ b/mojo/edk/system/raw_channel_win.cc
@@ -40,8 +40,8 @@
   }
 
  private:
-  typedef BOOL(WINAPI* SetFileCompletionNotificationModesFunc)(HANDLE, UCHAR);
-  typedef BOOL(WINAPI* CancelIoExFunc)(HANDLE, LPOVERLAPPED);
+  using SetFileCompletionNotificationModesFunc = BOOL(WINAPI*)(HANDLE, UCHAR);
+  using CancelIoExFunc = BOOL(WINAPI*)(HANDLE, LPOVERLAPPED);
 
   bool is_vista_or_higher_;
   SetFileCompletionNotificationModesFunc
diff --git a/mojo/edk/test/multiprocess_test_helper_unittest.cc b/mojo/edk/test/multiprocess_test_helper_unittest.cc
index 93496fb..4fe170c 100644
--- a/mojo/edk/test/multiprocess_test_helper_unittest.cc
+++ b/mojo/edk/test/multiprocess_test_helper_unittest.cc
@@ -40,7 +40,7 @@
   return bytes_read == 1;
 }
 
-typedef testing::Test MultiprocessTestHelperTest;
+using MultiprocessTestHelperTest = testing::Test;
 
 #if defined(OS_ANDROID)
 // Android multi-process tests are not executing the new process. This is flaky.