diff --git a/plugin/indent_guides.vim b/plugin/indent_guides.vim
index 47d3352..537bd02 100644
--- a/plugin/indent_guides.vim
+++ b/plugin/indent_guides.vim
@@ -4,6 +4,12 @@
 if exists('g:loaded_indent_guides') || &cp
   finish
 endif
+
+if !has('gui_running')
+  echoerr "The Indent Guides plugin requires gvim to work correctly."
+  finish
+end
+
 let g:loaded_indent_guides = 1
 
 function! s:IndentGuidesToggle()