diff --git a/lib/iControl.js b/lib/iControl.js
index 335089a..7f2bff9 100644
--- a/lib/iControl.js
+++ b/lib/iControl.js
@@ -24,50 +24,79 @@ var iControl = function(opts) {
 iControl.prototype.list = function(path, opts, cb) {
 
   // No options have been specified
-  if (arguments.length === 2) {
+  if (typeof opts === 'function') {
     cb = opts;
     opts = {};
   }
+  opts = opts || {};
 
-  // Options have been specified
-  else {
+  // Parse options
+  // TODO: support other options
+  var queryComponents = [];
+  if (opts.expandAll)    queryComponents.push('$expand=*');
+  if (opts.includeStats) queryComponents.push('$stats=true');
 
-    // Parse options
-    // TODO: support other options
-    var queryComponents = [];
-    if (opts.expandAll)    queryComponents.push('$expand=*');
-    if (opts.includeStats) queryComponents.push('$stats=true');
-
-    // Build query string
-    if (queryComponents.length !== 0) {
-      opts.query = '?' + queryComponents.join('&');
-    }
+  // Build query string
+  if (queryComponents.length !== 0) {
+    opts.query = '?' + queryComponents.join('&');
   }
+
   opts.path = path;
   opts.method = 'GET';
   this._request(opts, cb);
 };
 
 // Create
-iControl.prototype.create = function(path, body, cb) {
-  var opts = { path: path, body: body, method: 'POST' };
+iControl.prototype.create = function(path, body, opts, cb) {
+  // No options have been specified
+  if (typeof opts === 'function') {
+    cb = opts;
+    opts = {};
+  }
+  opts = opts || {};
+
+  opts.path = path;
+  opts.body = body;
+  opts.method = 'POST';
+
   this._request(opts, cb);
 };
 
 // Modify
-iControl.prototype.modify = function(path, body, cb) {
-  var opts = { path: path, body: body, method: 'PUT' };
+iControl.prototype.modify = function(path, body, opts, cb) {
+  // No options have been specified
+  if (typeof opts === 'function') {
+    cb = opts;
+    opts = {};
+  }
+  opts = opts || {};
+
+  opts.path = path;
+  opts.body = body;
+  opts.method = 'PUT';
+
   this._request(opts, cb);
 };
 
 // Delete
-iControl.prototype.delete = function(path, cb) {
-  var opts = { path: path, method: 'DELETE' };
+iControl.prototype.delete = function(path, opts, cb) {
+  // No options have been specified
+  if (typeof opts === 'function') {
+    cb = opts;
+    opts = {};
+  }
+  opts = opts || {};
+
+  opts.path = path;
+  opts.method = 'DELETE';
+
   this._request(opts, cb);
 };
 
 // Execute request
 iControl.prototype._request = function(opts, cb) {
+  var header;
+
   if (typeof opts.path !== 'string') return cb('URL must be specified', null);
   this.url = '/mgmt/tm' + opts.path;
   this.uri = this.proto + '://' + this.host + ':' + this.port + this.url;
@@ -87,11 +116,28 @@ iControl.prototype._request = function(opts, cb) {
   };
 
   // If body has been specified, add to request options
-  if (typeof opts.body === 'object') this.requestOpts.body = opts.body;
+  if (typeof opts.body === 'object' || typeof opts.body === 'string') this.requestOpts.body = opts.body;
 
   // If query string has been specified, add to request options
   if (typeof opts.query === 'string') this.requestOpts.qs = opts.query;
 
+  // If headers have been specified, add to request options
+  if (typeof opts.headers === 'object') {
+    this.requestOpts.headers = opts.headers;
+
+    // If we are specifying the content-type and it's not json, don't
+    // set json as a request option
+    for (header in opts.headers) {
+      if (opts.headers.hasOwnProperty(header)) {
+        if (header.toLowerCase() === 'content-type') {
+          if (opts.headers[header] !== 'application/json') {
+            this.requestOpts.json = false;
+          }
+        }
+      }
+    }
+  }
+
   // Do request
   request(this.requestOpts, function(err, res, body) {
 
@@ -112,7 +158,7 @@ iControl.prototype._request = function(opts, cb) {
 
       return cb(msg, false);
     }
-    
+
     // If retrieving via GET, handle pagination
     if (this.method === 'GET') {
 
@@ -126,7 +172,7 @@ iControl.prototype._request = function(opts, cb) {
         return cb(false, body);
       }
     }
-    
+
     // For POST/PUT/DELETE, return body
     else {
       return cb(false, body);