diff --git a/lib/program.js b/lib/program.js
index e3956b9..b23041e 100644
--- a/lib/program.js
+++ b/lib/program.js
@@ -260,8 +260,8 @@ Program.prototype.listen = function() {
   var keys = require('./keys')
     , self = this;
 
-  if (!this.input.isTTY || !this.output.isTTY) {
-    throw new Error('Not a terminal.');
+  if (!this.output.isTTY) {
+    // TODO: Add an ncurses-like warning.
   }
 
   // unshiftEvent(process, 'exit', function() {