diff --git a/example/main-io-context-server.cpp b/example/main-io-context-server.cpp
index bc491bfd..b82f207d 100644
--- a/example/main-io-context-server.cpp
+++ b/example/main-io-context-server.cpp
@@ -26,6 +26,7 @@
 #include <grpcpp/server_builder.h>
 
 #include <string_view>
+#include <thread>
 
 namespace asio = boost::asio;