diff --git a/tools/build_libvirt.sh b/tools/build_libvirt.sh
index 16259b1..48e2853 100755
--- a/tools/build_libvirt.sh
+++ b/tools/build_libvirt.sh
@@ -12,6 +12,27 @@ if [ ! "oneiric" = "$UBUNTU_VERSION" ]; then
     fi
 fi
 
+# Clean up any resources that may be in use
+cleanup() {
+    set +o errexit
+    unmount_images
+
+    if [ -n "$ROOTFS" ]; then
+        umount $ROOTFS/dev
+        umount $ROOTFS
+    fi
+
+    # Release NBD devices
+    if [ -n "$NBD" ]; then
+        qemu-nbd -d $NBD
+    fi
+
+    # Kill ourselves to signal any calling process
+    trap 2; kill -2 $$
+}
+
+trap cleanup SIGHUP SIGINT SIGTERM
+
 # Echo commands
 set -o xtrace
 
@@ -100,9 +121,6 @@ function kill_unmount() {
 # Install deps if needed
 dpkg -l kvm libvirt-bin kpartx || apt-get install -y --force-yes kvm libvirt-bin kpartx
 
-# Let Ctrl-c kill tail and exit
-trap kill_unmount SIGINT
-
 # Where Openstack code will live in image
 DEST=${DEST:-/opt/stack}
 
@@ -390,7 +408,9 @@ sed -e 's/^PasswordAuthentication.*$/PasswordAuthentication yes/' -i $ROOTFS/etc
 
 # Unmount
 umount $ROOTFS || echo 'ok'
+ROOTFS=""
 qemu-nbd -d $NBD
+NBD=""
 
 # Create the instance
 cd $VM_DIR && virsh create libvirt.xml
diff --git a/tools/build_pxe_boot.sh b/tools/build_pxe_boot.sh
index da8bbcc..ab64098 100755
--- a/tools/build_pxe_boot.sh
+++ b/tools/build_pxe_boot.sh
@@ -11,6 +11,22 @@ PXEDIR=${PXEDIR:-/var/cache/devstack/pxe}
 OPWD=`pwd`
 PROGDIR=`dirname $0`
 
+# Clean up any resources that may be in use
+cleanup() {
+    set +o errexit
+
+    # Mop up temporary files
+    if [ -n "$MNTDIR" -a -d "$MNTDIR" ]; then
+        umount $MNTDIR
+        rmdir $MNTDIR
+    fi
+
+    # Kill ourselves to signal any calling process
+    trap 2; kill -2 $$
+}
+
+trap cleanup SIGHUP SIGINT SIGTERM
+
 mkdir -p $DEST_DIR/pxelinux.cfg
 cd $DEST_DIR
 for i in memdisk menu.c32 pxelinux.0; do
diff --git a/tools/build_ramdisk.sh b/tools/build_ramdisk.sh
index 06e5857..187112a 100755
--- a/tools/build_ramdisk.sh
+++ b/tools/build_ramdisk.sh
@@ -10,6 +10,33 @@ if [ ! "$#" -eq "1" ]; then
     exit 1
 fi
 
+# Clean up any resources that may be in use
+cleanup() {
+    set +o errexit
+
+    # Mop up temporary files
+    if [ -n "$MNTDIR" -a -d "$MNTDIR" ]; then
+        umount $MNTDIR
+        rmdir $MNTDIR
+    fi
+    if [ -n "$DEV_FILE_TMP" -a -e "$DEV_FILE_TMP "]; then
+        rm -f $DEV_FILE_TMP
+    fi
+    if [ -n "$IMG_FILE_TMP" -a -e "$IMG_FILE_TMP" ]; then
+        rm -f $IMG_FILE_TMP
+    fi
+
+    # Release NBD devices
+    if [ -n "$NBD" ]; then
+        qemu-nbd -d $NBD
+    fi
+
+    # Kill ourselves to signal any calling process
+    trap 2; kill -2 $$
+}
+
+trap cleanup SIGHUP SIGINT SIGTERM
+
 # Set up nbd
 modprobe nbd max_part=63
 
@@ -107,6 +134,7 @@ if [ ! -r $DEV_FILE ]; then
     umount $MNTDIR
     rmdir $MNTDIR
     qemu-nbd -d $NBD
+    NBD=""
     mv $DEV_FILE_TMP $DEV_FILE
 fi
 rm -f $DEV_FILE_TMP
@@ -127,6 +155,7 @@ if [ ! -r $IMG_FILE ]; then
     dd if=${NBD}p1 of=$IMG_FILE_TMP bs=1M
 
     qemu-nbd -d $NBD
+    NBD=""
     mv $IMG_FILE_TMP $IMG_FILE
 fi
 rm -f $IMG_FILE_TMP
diff --git a/tools/build_usb_boot.sh b/tools/build_usb_boot.sh
index fc5e969..e4dabc0 100755
--- a/tools/build_usb_boot.sh
+++ b/tools/build_usb_boot.sh
@@ -11,6 +11,26 @@ PXEDIR=${PXEDIR:-/var/cache/devstack/pxe}
 OPWD=`pwd`
 PROGDIR=`dirname $0`
 
+# Clean up any resources that may be in use
+cleanup() {
+    set +o errexit
+
+    # Mop up temporary files
+    if [ -n "$DEST_DEV" ]; then
+        umount $DEST_DIR
+        rmdir $DEST_DIR
+    fi
+    if [ -n "$MNTDIR" -a -d "$MNTDIR" ]; then
+        umount $MNTDIR
+        rmdir $MNTDIR
+    fi
+
+    # Kill ourselves to signal any calling process
+    trap 2; kill -2 $$
+}
+
+trap cleanup SIGHUP SIGINT SIGTERM
+
 if [ -b $DEST_DIR ]; then
     # We have a block device, install syslinux and mount it
     DEST_DEV=$DEST_DIR
diff --git a/tools/get_uec_image.sh b/tools/get_uec_image.sh
index de37842..3d62bba 100755
--- a/tools/get_uec_image.sh
+++ b/tools/get_uec_image.sh
@@ -26,6 +26,24 @@ usage() {
     exit 1
 }
 
+# Clean up any resources that may be in use
+cleanup() {
+    set +o errexit
+
+    # Mop up temporary files
+    if [ -n "$IMG_FILE_TMP" -a -e "$IMG_FILE_TMP" ]; then
+        rm -f $IMG_FILE_TMP
+    fi
+
+    # Release NBD devices
+    if [ -n "$NBD" ]; then
+        qemu-nbd -d $NBD
+    fi
+
+    # Kill ourselves to signal any calling process
+    trap 2; kill -2 $$
+}
+
 while getopts f:hmr: c; do
     case $c in
         f)  FORMAT=$OPTARG
@@ -89,6 +107,8 @@ case $DIST_NAME in
                 ;;
 esac
 
+trap cleanup SIGHUP SIGINT SIGTERM
+
 # Prepare the base image
 
 # Get the UEC image
@@ -170,5 +190,6 @@ rm -f $MNTDIR/etc/resolv.conf
 umount $MNTDIR
 rmdir $MNTDIR
 qemu-nbd -d $NBD
+NBD=""
 
 mv $IMG_FILE_TMP $IMG_FILE