diff --git a/geocoder.admin.inc b/geocoder.admin.inc
index c4ca49b..b6a9cac 100644
--- a/geocoder.admin.inc
+++ b/geocoder.admin.inc
@@ -42,6 +42,22 @@ function geocoder_admin_settings($form, &$form_state) {
     '#size' => 10,
   );
 
+  $form['geocoder_client_google'] = array(
+    '#type' => 'textfield',
+    '#title' => t('Google Client Id'),
+    '#description' => t('The client ID identifies you as a Maps API for Business customer and enables support and purchased quota for your application'),
+    '#default_value' => empty($geocoder_settings['geocoder_client_google']) ? '' : $geocoder_settings['geocoder_client_google'],
+    '#required' => FALSE,
+  );
+
+  $form['geocoder_signature_google'] = array(
+    '#type' => 'textfield',
+    '#title' => t('Google Signature'),
+    '#description' => t('Your welcome letter includes a cryptographic signing key, which you must use to generate unique signatures for your web service requests.'),
+    '#default_value' => empty($geocoder_settings['geocoder_signature_google']) ? '' : $geocoder_settings['geocoder_signature_google'],
+    '#required' => FALSE,
+  );
+
   $form['#submit'][] = 'geocoder_admin_settings_submit';
   return system_settings_form($form);
 }
@@ -57,5 +73,7 @@ function geocoder_admin_settings_submit($form, &$form_state) {
   $geocoder_settings['geocoder_apikey_yahoo'] = trim($form_state['values']['geocoder_apikey_yahoo']);
   $geocoder_settings['geocoder_apikey_yandex'] = trim($form_state['values']['geocoder_apikey_yandex']);
   $geocoder_settings['geocoder_apikey_bing'] = trim($form_state['values']['geocoder_apikey_bing']);
+  $geocoder_settings['geocoder_signature_google'] = trim($form_state['values']['geocoder_signature_google']);
+  $geocoder_settings['geocoder_client_google'] = trim($form_state['values']['geocoder_client_google']);
   variable_set("geocoder_settings", $geocoder_settings);
 }
diff --git a/plugins/geocoder_handler/google.inc b/plugins/geocoder_handler/google.inc
index ea5a845..110cb5a 100755
--- a/plugins/geocoder_handler/google.inc
+++ b/plugins/geocoder_handler/google.inc
@@ -37,7 +37,23 @@ function geocoder_google($address, $options = array()) {
       'sensor' => 'false',
     );
 
+    $geocoder_settings = variable_get("geocoder_settings", array());
+    if (!empty($geocoder_settings["geocoder_client_google"])) {
+      $client_id = $geocoder_settings["geocoder_client_google"];
+    }
+    if (!empty($geocoder_settings["geocoder_signature_google"])) {
+      $signature = $geocoder_settings["geocoder_signature_google"];
+    }
+
+    if (isset($client_id)) {
+      $query['client'] = $client_id;
+    }
+
     $url = url("http://maps.googleapis.com/maps/api/geocode/json", array('query' => $query));
+    if (isset($signature)) {
+      $url = geocoder_google_sign_url($url, $signature);
+    }
+
     $result = drupal_http_request($url);
     $delay_trigger = TRUE;
 
@@ -145,6 +161,22 @@ function geocoder_google_field($field, $field_item, $options = array()) {
   }
 }
 
+/**
+ * Authenticates a Google API request with a signature.
+ */
+function geocoder_google_sign_url($input, $signature) {
+  $url_parts = parse_url($input);
+  $pathquery = $url_parts['path'] . "?" . $url_parts['query'];
+  $key = base64_decode(str_replace(array('-', '_'), array('+', '/'), $signature));
+
+  // Create a signature using the private key and the URL-encoded
+  // string using HMAC SHA1. This signature will be binary.
+  $hashed = hash_hmac("sha1", $pathquery, $key, TRUE);
+
+  $encoded_signature = str_replace(array('+', '/'), array('-', '_'), base64_encode($hashed));
+  return $input . "&signature=" . $encoded_signature;
+}
+
 function geocoder_google_form($default_values = array()) {
   $form = array();