diff --git a/README.md b/README.md
index b193a09..4f256c0 100644
--- a/README.md
+++ b/README.md
@@ -118,6 +118,77 @@ There are more scripts available in the [demos directory](demo/) that could help
 There are additional features that the program supports. Try using `mo --help` to see what is available.
 
 
+Enhancements
+-----------
+
+In addition to many of the features built-in to Mustache, `mo` includes a number of unique features that make it a bit more powerful.
+
+### Loop @key
+
+`mo` implements Handlebar's `@key` references for outputting the key inside of a loop:
+
+Env:
+```bash
+myarr=( foo bar )
+
+# Bash v4+
+declare -A myassoc
+myassoc[hello]="mo"
+myassoc[world]="is great"
+```
+
+Template:
+```handlebars
+{{#myarr}}
+ - {{@key}} {{.}}
+{{/myarr}}
+
+{{#myassoc}}
+ * {{@key}} {{.}}
+{{/myassoc}}
+```
+
+Output:
+```markdown
+ - 0 foo
+ - 1 bar
+
+ * hello mo
+ * world is great
+```
+
+
+### Helpers / Function Arguments with
+
+Function Arguments are not a part of the official Mustache implementation, and are more often associated with Handlebar's Helper functionality.
+
+`mo` allows for passing strings to functions.
+
+```handlebars
+{{myfunc foo bar}}
+```
+
+For security reasons, this arguments are not immediately available to function calls without a flag.
+
+#### with `--allow-function-arguments`
+
+```bash
+myfunc() {
+    # Outputs "foo, bar"
+    echo "$1, $2";
+}
+```
+
+#### Using `$MO_FUNCTION_ARGS`
+
+```bash
+myfunc() {
+    # Outputs "foo, bar"
+    echo "${MO_FUNCTION_ARGS[0]}, ${MO_FUNCTION_ARGS[1]}";
+}
+```
+
+
 Concessions
 -----------
 
diff --git a/mo b/mo
index c928d7c..bb14fbf 100755
--- a/mo
+++ b/mo
@@ -666,7 +666,7 @@ moLoop() {
 moParse() {
     # Keep naming variables mo* here to not overwrite needed variables
     # used in the string replacements
-    local moArgs moBlock moContent moCurrent moIsBeginning moNextIsBeginning moTag
+    local moArgs moBlock moContent moCurrent moIsBeginning moNextIsBeginning moTag moKey
 
     moCurrent=$2
     moIsBeginning=$3
@@ -782,6 +782,17 @@ moParse() {
                 moShow "$moTag" "$moCurrent"
                 ;;
 
+            '@key')
+                # Special vars
+                moStandaloneDenied moContent "${moContent[@]}"
+                # Current content (environment variable or function)
+                if [[ "$moCurrent" == *.* ]]; then
+                    echo -n "${moCurrent#*.}"
+                else
+                    echo -n "$moCurrent"
+                fi
+                ;;
+
             *)
                 # Normal environment variable or function call
                 moStandaloneDenied moContent "${moContent[@]}"
diff --git a/tests/array.expected b/tests/array.expected
index a45557c..94d9b8e 100644
--- a/tests/array.expected
+++ b/tests/array.expected
@@ -1,3 +1,3 @@
-  <b>resque</b>
-  <b>hub</b>
-  <b>rip</b>
+  <b>0 - resque</b>
+  <b>1 - hub</b>
+  <b>2 - rip</b>
diff --git a/tests/array.template b/tests/array.template
index 4c61e9c..8671607 100644
--- a/tests/array.template
+++ b/tests/array.template
@@ -1,3 +1,3 @@
 {{#repo}}
-  <b>{{.}}</b>
+  <b>{{@index}} - {{.}}</b>
 {{/repo}}
diff --git a/tests/assoc-array.env b/tests/assoc-array.env
new file mode 100644
index 0000000..934cade
--- /dev/null
+++ b/tests/assoc-array.env
@@ -0,0 +1,4 @@
+declare -A repo
+repo[resque]="Resque"
+repo[hub]="Hub"
+repo[rip]="Rip"
diff --git a/tests/assoc-array.expected b/tests/assoc-array.expected
new file mode 100644
index 0000000..6ef4ced
--- /dev/null
+++ b/tests/assoc-array.expected
@@ -0,0 +1,3 @@
+  <b>hub - Hub</b>
+  <b>rip - Rip</b>
+  <b>resque - Resque</b>
diff --git a/tests/assoc-array.template b/tests/assoc-array.template
new file mode 100644
index 0000000..771906f
--- /dev/null
+++ b/tests/assoc-array.template
@@ -0,0 +1,3 @@
+{{#repo}}
+  <b>{{@key}} - {{.}}</b>
+{{/repo}}