diff --git a/include/xo/expression2/Constant.hpp b/include/xo/expression2/Constant.hpp
new file mode 100644
index 00000000..29e6694f
--- /dev/null
+++ b/include/xo/expression2/Constant.hpp
@@ -0,0 +1,13 @@
+/** @file Constant.hpp
+ *
+ *  @author Roland Conybeare, Feb 2026
+ **/
+
+#pragma once
+
+#include "DConstant.hpp"
+#include "detail/IExpression_DConstant.hpp"
+#include "detail/IGCObject_DConstant.hpp"
+#include "detail/IPrintable_DConstant.hpp"
+
+/* end Constant.hpp */