--- a/src/libcmis/oauth2-handler.cxx
+++ b/src/libcmis/oauth2-handler.cxx
@@ -26,6 +26,8 @@
  * instead of those above.
  */
 
+#include <boost/algorithm/string.hpp>
+
 #include "oauth2-handler.hxx"
 
 #include <libcmis/session-factory.hxx>