diff --git a/CHANGELOG.md b/CHANGELOG.md
index da35554b..90b45a8f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,9 @@
+Version 154:
+
+* Type check completion handlers
+
+--------------------------------------------------------------------------------
+
 Version 153:
 
 * Remove BOOST_VERSION checks
diff --git a/include/boost/beast/core/detail/type_traits.hpp b/include/boost/beast/core/detail/type_traits.hpp
index c85cfe73..f07697c9 100644
--- a/include/boost/beast/core/detail/type_traits.hpp
+++ b/include/boost/beast/core/detail/type_traits.hpp
@@ -437,6 +437,18 @@ buffers_range(Buffers const& buffers)
     return buffers_range_adaptor<Buffers>{buffers};
 }
 
+/*  If this static assert goes off, it means that the completion
+    handler you provided to an asynchronous initiating function did
+    not have the right signature. Check the parameter types for your
+    completion handler and make sure they match the list of types
+    expected by the initiating function,
+*/
+#define BOOST_BEAST_HANDLER_INIT(type, sig) \
+    static_assert(is_completion_handler< \
+    BOOST_ASIO_HANDLER_TYPE(type, sig), sig>::value, \
+    "CompletionHandler signature requirements not met"); \
+    boost::asio::async_completion<type, sig> init{handler}
+
 } // detail
 } // beast
 } // boost
diff --git a/include/boost/beast/core/impl/buffered_read_stream.ipp b/include/boost/beast/core/impl/buffered_read_stream.ipp
index 139c66a7..09f76345 100644
--- a/include/boost/beast/core/impl/buffered_read_stream.ipp
+++ b/include/boost/beast/core/impl/buffered_read_stream.ipp
@@ -233,8 +233,8 @@ async_read_some(
     if(buffer_.size() == 0 && capacity_ == 0)
         return next_layer_.async_read_some(buffers,
             std::forward<ReadHandler>(handler));
-    boost::asio::async_completion<ReadHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        ReadHandler, void(error_code, std::size_t));
     read_some_op<MutableBufferSequence, BOOST_ASIO_HANDLER_TYPE(
         ReadHandler, void(error_code, std::size_t))>{
             std::move(init.completion_handler), *this, buffers}(
diff --git a/include/boost/beast/http/impl/file_body_win32.ipp b/include/boost/beast/http/impl/file_body_win32.ipp
index 9e4cfaf8..a0d8e606 100644
--- a/include/boost/beast/http/impl/file_body_win32.ipp
+++ b/include/boost/beast/http/impl/file_body_win32.ipp
@@ -564,8 +564,8 @@ async_write_some(
         basic_file_body<file_win32>, Fields>& sr,
     WriteHandler&& handler)
 {
-    boost::asio::async_completion<WriteHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        WriteHandler, void(error_code, std::size_t));
     detail::write_some_win32_op<
         Protocol,
         BOOST_ASIO_HANDLER_TYPE(WriteHandler,
diff --git a/include/boost/beast/http/impl/read.ipp b/include/boost/beast/http/impl/read.ipp
index df0eb690..4a847a2a 100644
--- a/include/boost/beast/http/impl/read.ipp
+++ b/include/boost/beast/http/impl/read.ipp
@@ -526,8 +526,8 @@ async_read_some(
         boost::asio::is_dynamic_buffer<DynamicBuffer>::value,
         "DynamicBuffer requirements not met");
     BOOST_ASSERT(! parser.is_done());
-    boost::asio::async_completion<ReadHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        ReadHandler, void(error_code, std::size_t));
     detail::read_some_op<AsyncReadStream,
         DynamicBuffer, isRequest, Derived, BOOST_ASIO_HANDLER_TYPE(
             ReadHandler, void(error_code, std::size_t))>{
@@ -614,8 +614,8 @@ async_read_header(
         boost::asio::is_dynamic_buffer<DynamicBuffer>::value,
         "DynamicBuffer requirements not met");
     parser.eager(false);
-    boost::asio::async_completion<ReadHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        ReadHandler, void(error_code, std::size_t));
     detail::read_op<AsyncReadStream, DynamicBuffer,
         isRequest, Derived, detail::parser_is_header_done,
             BOOST_ASIO_HANDLER_TYPE(ReadHandler, void(error_code, std::size_t))>{
@@ -702,9 +702,8 @@ async_read(
         boost::asio::is_dynamic_buffer<DynamicBuffer>::value,
         "DynamicBuffer requirements not met");
     parser.eager(true);
-    boost::asio::async_completion<
-        ReadHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        ReadHandler, void(error_code, std::size_t));
     detail::read_op<AsyncReadStream, DynamicBuffer,
         isRequest, Derived, detail::parser_is_done,
             BOOST_ASIO_HANDLER_TYPE(ReadHandler, void(error_code, std::size_t))>{
@@ -794,9 +793,8 @@ async_read(
         "Body requirements not met");
     static_assert(is_body_reader<Body>::value,
         "BodyReader requirements not met");
-    boost::asio::async_completion<
-        ReadHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        ReadHandler, void(error_code, std::size_t));
     detail::read_msg_op<
         AsyncReadStream,
         DynamicBuffer,
diff --git a/include/boost/beast/http/impl/write.ipp b/include/boost/beast/http/impl/write.ipp
index 10cd26ef..6ef13864 100644
--- a/include/boost/beast/http/impl/write.ipp
+++ b/include/boost/beast/http/impl/write.ipp
@@ -471,9 +471,8 @@ async_write_some_impl(
     serializer<isRequest, Body, Fields>& sr,
     WriteHandler&& handler)
 {
-    boost::asio::async_completion<
-        WriteHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        WriteHandler, void(error_code, std::size_t));
     detail::write_some_op<
         AsyncWriteStream,
         BOOST_ASIO_HANDLER_TYPE(WriteHandler,
@@ -629,9 +628,8 @@ async_write_header(
     static_assert(is_body_writer<Body>::value,
         "BodyWriter requirements not met");
     sr.split(true);
-    boost::asio::async_completion<
-        WriteHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        WriteHandler, void(error_code, std::size_t));
     detail::write_op<
         AsyncWriteStream,
         BOOST_ASIO_HANDLER_TYPE(WriteHandler,
@@ -706,9 +704,8 @@ async_write(
     static_assert(is_body_writer<Body>::value,
         "BodyWriter requirements not met");
     sr.split(false);
-    boost::asio::async_completion<
-        WriteHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        WriteHandler, void(error_code, std::size_t));
     detail::write_op<
         AsyncWriteStream,
         BOOST_ASIO_HANDLER_TYPE(WriteHandler,
@@ -780,9 +777,8 @@ async_write(
         "Body requirements not met");
     static_assert(is_body_writer<Body>::value,
         "BodyWriter requirements not met");
-    boost::asio::async_completion<
-        WriteHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        WriteHandler, void(error_code, std::size_t));
     detail::write_msg_op<
         AsyncWriteStream,
         BOOST_ASIO_HANDLER_TYPE(WriteHandler,
diff --git a/include/boost/beast/websocket/impl/accept.ipp b/include/boost/beast/websocket/impl/accept.ipp
index 0dff87d2..21c920f8 100644
--- a/include/boost/beast/websocket/impl/accept.ipp
+++ b/include/boost/beast/websocket/impl/accept.ipp
@@ -544,8 +544,8 @@ async_accept(
 {
     static_assert(is_async_stream<next_layer_type>::value,
         "AsyncStream requirements not met");
-    boost::asio::async_completion<AcceptHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        AcceptHandler, void(error_code));
     reset();
     accept_op<
         decltype(&default_decorate_res),
@@ -573,8 +573,8 @@ async_accept_ex(
     static_assert(detail::is_response_decorator<
         ResponseDecorator>::value,
             "ResponseDecorator requirements not met");
-    boost::asio::async_completion<AcceptHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        AcceptHandler, void(error_code));
     reset();
     accept_op<
         ResponseDecorator,
@@ -604,8 +604,8 @@ async_accept(
     static_assert(boost::asio::is_const_buffer_sequence<
         ConstBufferSequence>::value,
             "ConstBufferSequence requirements not met");
-    boost::asio::async_completion<AcceptHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        AcceptHandler, void(error_code));
     reset();
     accept_op<
         decltype(&default_decorate_res),
@@ -640,8 +640,8 @@ async_accept_ex(
     static_assert(detail::is_response_decorator<
         ResponseDecorator>::value,
             "ResponseDecorator requirements not met");
-    boost::asio::async_completion<AcceptHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        AcceptHandler, void(error_code));
     reset();
     accept_op<
         ResponseDecorator,
@@ -666,8 +666,8 @@ async_accept(
 {
     static_assert(is_async_stream<next_layer_type>::value,
         "AsyncStream requirements not met");
-    boost::asio::async_completion<AcceptHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        AcceptHandler, void(error_code));
     reset();
     using boost::asio::asio_handler_is_continuation;
     response_op<
@@ -698,8 +698,8 @@ async_accept_ex(
     static_assert(detail::is_response_decorator<
         ResponseDecorator>::value,
             "ResponseDecorator requirements not met");
-    boost::asio::async_completion<AcceptHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        AcceptHandler, void(error_code));
     reset();
     using boost::asio::asio_handler_is_continuation;
     response_op<
diff --git a/include/boost/beast/websocket/impl/close.ipp b/include/boost/beast/websocket/impl/close.ipp
index 17697139..b925ba8d 100644
--- a/include/boost/beast/websocket/impl/close.ipp
+++ b/include/boost/beast/websocket/impl/close.ipp
@@ -435,8 +435,8 @@ async_close(close_reason const& cr, CloseHandler&& handler)
 {
     static_assert(is_async_stream<next_layer_type>::value,
         "AsyncStream requirements not met");
-    boost::asio::async_completion<CloseHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        CloseHandler, void(error_code));
     close_op<BOOST_ASIO_HANDLER_TYPE(
         CloseHandler, void(error_code))>{
             std::move(init.completion_handler), *this, cr}(
diff --git a/include/boost/beast/websocket/impl/handshake.ipp b/include/boost/beast/websocket/impl/handshake.ipp
index edab6542..644ca5c2 100644
--- a/include/boost/beast/websocket/impl/handshake.ipp
+++ b/include/boost/beast/websocket/impl/handshake.ipp
@@ -160,8 +160,8 @@ async_handshake(string_view host,
 {
     static_assert(is_async_stream<next_layer_type>::value,
         "AsyncStream requirements not met");
-    boost::asio::async_completion<HandshakeHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        HandshakeHandler, void(error_code));
     handshake_op<BOOST_ASIO_HANDLER_TYPE(
         HandshakeHandler, void(error_code))>{
             std::move(init.completion_handler), *this, nullptr, host,
@@ -181,8 +181,8 @@ async_handshake(response_type& res,
 {
     static_assert(is_async_stream<next_layer_type>::value,
         "AsyncStream requirements not met");
-    boost::asio::async_completion<HandshakeHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        HandshakeHandler, void(error_code));
     handshake_op<BOOST_ASIO_HANDLER_TYPE(
         HandshakeHandler, void(error_code))>{
             std::move(init.completion_handler), *this, &res, host,
@@ -205,8 +205,8 @@ async_handshake_ex(string_view host,
     static_assert(detail::is_request_decorator<
             RequestDecorator>::value,
         "RequestDecorator requirements not met");
-    boost::asio::async_completion<HandshakeHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        HandshakeHandler, void(error_code));
     handshake_op<BOOST_ASIO_HANDLER_TYPE(
         HandshakeHandler, void(error_code))>{
             std::move(init.completion_handler), *this, nullptr, host,
@@ -230,8 +230,8 @@ async_handshake_ex(response_type& res,
     static_assert(detail::is_request_decorator<
             RequestDecorator>::value,
         "RequestDecorator requirements not met");
-    boost::asio::async_completion<HandshakeHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        HandshakeHandler, void(error_code));
     handshake_op<BOOST_ASIO_HANDLER_TYPE(
         HandshakeHandler, void(error_code))>{
             std::move(init.completion_handler), *this, &res, host,
diff --git a/include/boost/beast/websocket/impl/ping.ipp b/include/boost/beast/websocket/impl/ping.ipp
index f4067548..25303aa8 100644
--- a/include/boost/beast/websocket/impl/ping.ipp
+++ b/include/boost/beast/websocket/impl/ping.ipp
@@ -237,8 +237,8 @@ async_ping(ping_data const& payload, WriteHandler&& handler)
 {
     static_assert(is_async_stream<next_layer_type>::value,
         "AsyncStream requirements not met");
-    boost::asio::async_completion<WriteHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        WriteHandler, void(error_code));
     ping_op<BOOST_ASIO_HANDLER_TYPE(
         WriteHandler, void(error_code))>{
             std::move(init.completion_handler), *this,
@@ -255,8 +255,8 @@ async_pong(ping_data const& payload, WriteHandler&& handler)
 {
     static_assert(is_async_stream<next_layer_type>::value,
         "AsyncStream requirements not met");
-    boost::asio::async_completion<WriteHandler,
-        void(error_code)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        WriteHandler, void(error_code));
     ping_op<BOOST_ASIO_HANDLER_TYPE(
         WriteHandler, void(error_code))>{
             std::move(init.completion_handler), *this,
diff --git a/include/boost/beast/websocket/impl/read.ipp b/include/boost/beast/websocket/impl/read.ipp
index b27149bd..60999ef6 100644
--- a/include/boost/beast/websocket/impl/read.ipp
+++ b/include/boost/beast/websocket/impl/read.ipp
@@ -895,8 +895,8 @@ async_read(DynamicBuffer& buffer, ReadHandler&& handler)
     static_assert(
         boost::asio::is_dynamic_buffer<DynamicBuffer>::value,
         "DynamicBuffer requirements not met");
-    boost::asio::async_completion<
-        ReadHandler, void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        ReadHandler, void(error_code, std::size_t));
     read_op<
         DynamicBuffer,
         BOOST_ASIO_HANDLER_TYPE(
@@ -983,8 +983,8 @@ async_read_some(
     static_assert(
         boost::asio::is_dynamic_buffer<DynamicBuffer>::value,
         "DynamicBuffer requirements not met");
-    boost::asio::async_completion<ReadHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        ReadHandler, void(error_code, std::size_t));
     read_op<
         DynamicBuffer,
         BOOST_ASIO_HANDLER_TYPE(
@@ -1368,8 +1368,8 @@ async_read_some(
     static_assert(boost::asio::is_mutable_buffer_sequence<
             MutableBufferSequence>::value,
         "MutableBufferSequence requirements not met");
-    boost::asio::async_completion<ReadHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        ReadHandler, void(error_code, std::size_t));
     read_some_op<MutableBufferSequence, BOOST_ASIO_HANDLER_TYPE(
         ReadHandler, void(error_code, std::size_t))>{
             std::move(init.completion_handler), *this, buffers}(
diff --git a/include/boost/beast/websocket/impl/write.ipp b/include/boost/beast/websocket/impl/write.ipp
index eccde945..ab71aba9 100644
--- a/include/boost/beast/websocket/impl/write.ipp
+++ b/include/boost/beast/websocket/impl/write.ipp
@@ -814,8 +814,8 @@ async_write_some(bool fin,
     static_assert(boost::asio::is_const_buffer_sequence<
         ConstBufferSequence>::value,
             "ConstBufferSequence requirements not met");
-    boost::asio::async_completion<WriteHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        WriteHandler, void(error_code, std::size_t));
     write_some_op<ConstBufferSequence, BOOST_ASIO_HANDLER_TYPE(
         WriteHandler, void(error_code, std::size_t))>{
             std::move(init.completion_handler), *this, fin, bs}(
@@ -870,8 +870,8 @@ async_write(
     static_assert(boost::asio::is_const_buffer_sequence<
         ConstBufferSequence>::value,
             "ConstBufferSequence requirements not met");
-    boost::asio::async_completion<WriteHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        WriteHandler, void(error_code, std::size_t));
     write_some_op<ConstBufferSequence, BOOST_ASIO_HANDLER_TYPE(
         WriteHandler, void(error_code, std::size_t))>{
             std::move(init.completion_handler), *this, true, bs}(
diff --git a/test/extras/include/boost/beast/test/stream.hpp b/test/extras/include/boost/beast/test/stream.hpp
index a75bbde4..8a2730d7 100644
--- a/test/extras/include/boost/beast/test/stream.hpp
+++ b/test/extras/include/boost/beast/test/stream.hpp
@@ -479,8 +479,8 @@ async_read_some(
     using boost::asio::buffer_copy;
     using boost::asio::buffer_size;
     BOOST_ASSERT(buffer_size(buffers) > 0);
-    boost::asio::async_completion<ReadHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        ReadHandler, void(error_code, std::size_t));
     if(in_->fc)
     {
         error_code ec;
@@ -598,8 +598,8 @@ async_write_some(ConstBufferSequence const& buffers,
         "ConstBufferSequence requirements not met");
     using boost::asio::buffer_copy;
     using boost::asio::buffer_size;
-    boost::asio::async_completion<WriteHandler,
-        void(error_code, std::size_t)> init{handler};
+    BOOST_BEAST_HANDLER_INIT(
+        WriteHandler, void(error_code, std::size_t));
     auto out = out_.lock();
     if(! out)
         return boost::asio::post(