diff --git a/bin/disk-image-create b/bin/disk-image-create
index 45d8024b..415cbaf9 100755
--- a/bin/disk-image-create
+++ b/bin/disk-image-create
@@ -133,7 +133,7 @@ function show_options () {
     echo "    --docker-target -- specify the repo and tag to use if the output type is docker. Defaults to the value of output imagename"
     if [ "$IS_RAMDISK" == "0" ]; then
         echo "    -n skip the default inclusion of the 'base' element"
-        echo "    -p package[,package,package] -- list of packages to install in the image"
+        echo "    -p package[,package,package] -- list of packages to install in the image. If specified multiple times the packages are appended to the list."
     fi
     echo "    -h|--help -- display this help and exit"
     echo "    --version -- display version and exit"
@@ -190,7 +190,7 @@ while true ; do
         -u) shift; export COMPRESS_IMAGE="";;
         -c) shift ; export CLEAR_ENV=1;;
         -n) shift; export SKIP_BASE="1";;
-        -p) IFS="," read -a INSTALL_PACKAGES <<< "$2"; export INSTALL_PACKAGES ; shift 2 ;;
+        -p) IFS="," read -a _INSTALL_PACKAGES <<< "$2"; export INSTALL_PACKAGES=( ${INSTALL_PACKAGES[@]} ${_INSTALL_PACKAGES[@]} ) ; shift 2 ;;
         --checksum) shift; export DIB_CHECKSUM=1;;
         --image-size) export DIB_IMAGE_SIZE=$2; shift 2;;
         --image-cache) export DIB_IMAGE_CACHE=$2; shift 2;;