diff --git a/IOStreams/OStreamable.h b/IOStreams/OStreamable.h
index 15c8951..87e5c3b 100644
--- a/IOStreams/OStreamable.h
+++ b/IOStreams/OStreamable.h
@@ -9,6 +9,7 @@ static_assert( __cplusplus > 2020'99 );
 #include <Alepha/Capabilities.h>
 #include <Alepha/template_for_each.h>
 #include <Alepha/string_algorithms.h>
+#include <Alepha/delimited_list.h>
 #include <Alepha/Concepts.h>
 
 #include <Alepha/Reflection/tuplizeAggregate.h>