diff --git a/README.md b/README.md
index ddc17ec..e8155fe 100644
--- a/README.md
+++ b/README.md
@@ -88,10 +88,24 @@ OUTPUT
  -l, --outputlist <outputfile-1...outputfile-n> Output to named files for each scanned page, can be used with append
 ```
 
+### Configuration
+
+Use `--help` locally to show the location of optional configuration and
+pre-scan hook scripts. These scripts may contain environment variables to
+pre-configure `scan`. For example the contents of the `default` file may be
+something like:
+
+```
+DEVICE=something
+SEARCHABLE=1
+MODE_HW_DEFAULT=1
+```
+
 ### Tips
 
 The default scanner device is set to `fujitsu`. If you have another scanner,
-you will need to use the `-x`/`--device` argument to specify your scanner.
+you will need to use the `-x`/`--device` argument to specify your scanner,
+or save a `DEVICE=something` line to a local config file as shown above.
 See below for how to get the list of available devices.
 
 The scanners and scanner drivers vary in features they support. This script
diff --git a/scan b/scan
index 4572c05..3d6fd2c 100755
--- a/scan
+++ b/scan
@@ -40,7 +40,9 @@ cleanup()
 }
 trap cleanup EXIT
 
-[ -e "${XDG_DATA_HOME:-$HOME/.local/share}/sane-scan-pdf/defaults" ] && . "${XDG_DATA_HOME:-$HOME/.local/share}/sane-scan-pdf/defaults"
+DEFAULTS="${XDG_DATA_HOME:-$HOME/.local/share}/sane-scan-pdf/defaults"
+SCANPRE="${XDG_DATA_HOME:-$HOME/.local/share}/sane-scan-pdf/scan_pre"
+[ -e "$DEFAULTS" ] && . "$DEFAULTS"
 
 # Parse command-line options
 while [[ $# > 0 ]]; do
@@ -149,6 +151,13 @@ if [[ $HELP == 1 ]]; then
   echo "   Output to named file default=scan.pdf"
   echo " -l, --outputlist <outputfile-1...outputfile-n> Output to named files for each scanned page, can be used with append"
   echo ""
+  echo "CONFIGURATION"
+  echo "Local configuration can be written in the form of environment variables to:"
+  echo "  $DEFAULTS"
+  echo ""
+  echo "A pre-scan hook script can be written to:"
+  echo "  $SCANPRE"
+  echo ""
   exit 0
 fi
 
@@ -272,7 +281,7 @@ if [[ $MODE_HW_DEFAULT == 1 ]]; then
 else
   MODE="--mode '$MODE'"
 fi
-[ -e "${XDG_DATA_HOME:-$HOME/.local/share}/sane-scan-pdf/scan_pre" ] && . "${XDG_DATA_HOME:-$HOME/.local/share}/sane-scan-pdf/scan_pre"
+[ -e "$SCANPRE" ] && . "$SCANPRE"
 eval scanadf -d \'"$DEVICE"\' $MAXPAGE $PGHEIGHT $PGWIDTH -S $SCRIPT --script-wait $DESKEW $CROP $DRIVER_OPTION $SOURCE --resolution $RESOLUTION $MODE -o $TMP_DIR/scan-%04d
 # Simulate empty page scanner outputs for debugging
 #convert xc:none -page Letter $TMP_DIR/scan-0001.pdf