diff --git a/org/qmckl_point.org b/org/qmckl_point.org
index aa2ba2a..592e7a3 100644
--- a/org/qmckl_point.org
+++ b/org/qmckl_point.org
@@ -283,6 +283,13 @@ qmckl_set_point (qmckl_context context,
     return QMCKL_NULL_CONTEXT;
   }
 
+  if (num <= 0) {
+      return qmckl_failwith( context,
+                             QMCKL_INVALID_ARG_4,
+                             "qmckl_set_point",
+                             "Number of points should be >0.");
+  }
+
   if (size_max < 3*num) {
       return qmckl_failwith( context,
                              QMCKL_INVALID_ARG_4,