diff --git a/config.vim b/config.vim
index ec010f2..1569d0e 100644
--- a/config.vim
+++ b/config.vim
@@ -10,6 +10,8 @@
 
 " Always show the current cursor position.
 set ruler
+" Show the 80 character column.
+set colorcolumn=80
 " Show line numbers.
 set number