diff --git a/asio/src/doc/design/proactor_dox.txt b/asio/src/doc/design/proactor_dox.txt
index 59da46ab..b2cf2b8a 100644
--- a/asio/src/doc/design/proactor_dox.txt
+++ b/asio/src/doc/design/proactor_dox.txt
@@ -79,7 +79,7 @@ completion port. There is one I/O completion port for each asio::demuxer
 instance.
 
 @par Asynchronous Event Demultiplexer
-called by asio to dequeue events and their associated completion handlers.
+Called by asio to dequeue events and their associated completion handlers.
 
 \section designproactoradv Advantages