diff --git a/transliteration.install b/transliteration.install
index ccbf7c4..f25581c 100644
--- a/transliteration.install
+++ b/transliteration.install
@@ -29,6 +29,7 @@ function transliteration_install() {
 function transliteration_uninstall() {
   variable_del('transliteration_file_uploads');
   variable_del('transliteration_file_lowercase');
+  variable_del('transliteration_file_space_replacement');
   variable_del('transliteration_search');
 }
 
diff --git a/transliteration.module b/transliteration.module
index c98ab51..d393ae0 100644
--- a/transliteration.module
+++ b/transliteration.module
@@ -69,6 +69,16 @@ function transliteration_form_system_file_system_settings_alter(&$form, &$form_s
       ),
     ),
   );
+  $form['transliteration']['transliteration_file_space_replacement'] = array(
+    '#type' => 'radios',
+    '#title' => t('Replace spaces with'),
+    '#default_value' => variable_get('transliteration_file_space_replacement', '_'),
+    '#description' => t('Select what character to use when replacing white space in file names. It has no effect if transliteration has been disabled.'),
+    '#options' => array(
+      '-' => t('Hyphen (-)'),
+      '_' => t('Underscore (_)'),
+    ),
+  );
   $form['buttons']['#weight'] = 1;
 }
 
@@ -123,7 +133,7 @@ function transliteration_clean_filename($filename, $source_langcode = NULL) {
   drupal_alter('transliteration_clean_filename_prepare', $filename, $source_langcode);
   $filename = transliteration_get($filename, '', $source_langcode);
   // Replace whitespace.
-  $filename = str_replace(' ', '_', $filename);
+  $filename = str_replace(' ', variable_get('transliteration_file_space_replacement', '_'), $filename);
   // Remove remaining unsafe characters.
   $filename = preg_replace('![^0-9A-Za-z_.-]!', '', $filename);
   // Remove multiple consecutive non-alphabetical characters.