diff --git a/completion.sh b/completion.sh
index 56d28896..264cafce 100644
--- a/completion.sh
+++ b/completion.sh
@@ -1,11 +1,37 @@
-_setup_bench_tab_completion () {
-	if [ -n "$BASH" ] ; then
-		eval "$(_BENCH_COMPLETE=source bench)"
-	elif [ -n "$ZSH_VERSION" ]; then
-		autoload bashcompinit
-		bashcompinit
-		eval "$(_BENCH_COMPLETE=source bench)"
-	fi
+_bench_completion() {
+    # Complete commands using click bashcomplete
+    COMPREPLY=( $( COMP_WORDS="${COMP_WORDS[*]}" \
+                   COMP_CWORD=$COMP_CWORD \
+                   _BENCH_COMPLETE=complete $1 ) )
+    if [ -d "sites" ]; then
+        # Also add frappe commands if present
+
+        # bench_helper.py expects to be executed from "sites" directory
+        cd sites
+
+        # All frappe commands are subcommands under "bench frappe"
+        # Frappe is only installed in virtualenv "env" so use appropriate python executable
+        COMPREPLY+=( $( COMP_WORDS="bench frappe "${COMP_WORDS[@]:1} \
+                        COMP_CWORD=$(($COMP_CWORD+1)) \
+                        _BENCH_COMPLETE=complete ../env/bin/python ../apps/frappe/frappe/utils/bench_helper.py ) )
+
+        # If the word before the current cursor position in command typed so far is "--site" then only list sites
+        if [ ${COMP_WORDS[COMP_CWORD-1]} == "--site" ]; then
+            COMPREPLY=( $( ls -d ./*/site_config.json | cut -f 2 -d "/" | xargs echo ) )
+        fi
+
+        # Get out of sites directory now
+        cd ..
+    fi
+    return 0
 }
 
-_setup_bench_tab_completion
+# Only support bash and zsh
+if [ -n "$BASH" ] ; then
+    complete -F _bench_completion -o default bench;
+elif [ -n "$ZSH_VERSION" ]; then
+    # Use zsh in bash compatibility mode
+    autoload bashcompinit
+    bashcompinit
+    complete -F _bench_completion -o default bench;
+fi