diff --git a/DESCRIPTION b/DESCRIPTION
index 4092c8312a7ce2fc2c03c52b8ae8d2b62d3a2062..030f20002ab7b78484166f93cf668e509202b2b2 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -43,6 +43,7 @@ Suggests:
     reshape2,
     MASS,
     qcc,
-    multcomp
+    multcomp,
+    vcd
 VignetteBuilder: knitr
 RoxygenNote: 5.0.1