diff --git a/tests/t1550-done.sh b/tests/t1550-done.sh
new file mode 100755
index 0000000..583ae70
--- /dev/null
+++ b/tests/t1550-done.sh
@@ -0,0 +1,52 @@
+#!/bin/sh
+
+test_description='done functionality
+'
+. ./test-lib.sh
+
+#DATE=`date '+%Y-%m-%d'`
+
+test_todo_session 'done usage' <<EOF
+>>> export TODOTXT_FORCE=1
+
+>>> todo.sh done
+usage: todo.sh done "TODO ITEM"
+=== 1
+EOF
+
+cat > todo.txt <<EOF
+stop
+remove1
+remove2
+remove3
+remove4
+EOF
+
+test_todo_session 'basic done' <<EOF
+>>> todo.sh lsa 
+2 remove1
+3 remove2
+4 remove3
+5 remove4
+1 stop
+--
+TODO: 5 of 5 tasks shown
+
+>>> todo.sh done smell the uppercase Roses
+TODO: 'smell the uppercase Roses' marked as done.
+
+>>> todo.sh done notice the sunflowers    
+TODO: 'notice the sunflowers' marked as done.
+
+>>> todo.sh lsa
+2 remove1
+3 remove2
+4 remove3
+5 remove4
+1 stop
+7 x 2009-02-13 notice the sunflowers
+6 x 2009-02-13 smell the uppercase Roses
+--
+TODO: 7 of 7 tasks shown
+EOF
+test_done
diff --git a/todo.sh b/todo.sh
index 3cbebe3..640b348 100755
--- a/todo.sh
+++ b/todo.sh
@@ -799,6 +799,26 @@ case $action in
     fi
     cleanup ;;
 
+"done" )
+    if [[ -z "$2" && $TODOTXT_FORCE = 0 ]]; then
+        echo -n "Done: "
+        read input
+    else
+        [ -z "$2" ] && die "usage: $TODO_SH done \"TODO ITEM\""
+        shift
+        input=$*
+    fi
+
+    now=`date '+%Y-%m-%d'`
+    # remove priority once item is done
+    newtodo=$(sed -e "s/^(.) // ; s|^|&x $now |" <<<${input})
+    echo "$newtodo" >> "$DONE_FILE"
+    [ $TODOTXT_VERBOSE -gt 0 ] && {
+        echo "TODO: '$input' marked as done."
+    }
+
+    cleanup;;
+
 "help" )
     if [ -t 1 ] ; then # STDOUT is a TTY
         if (exec which ${PAGER:-less} 2>/dev/null >/dev/null); then