diff --git a/packages/meteor-base/package.js b/packages/meteor-base/package.js
index c2c552de06..25ba9fefe8 100644
--- a/packages/meteor-base/package.js
+++ b/packages/meteor-base/package.js
@@ -18,6 +18,9 @@ Package.onUse(function(api) {
     // removable
     'webapp',
 
+    // Most Meteor core packages depend on Underscore right now
+    'underscore',
+
     // The protocol and client/server libraries that Meteor uses to send data
     'ddp',
     'livedata', // XXX COMPAT WITH PACKAGES BUILT FOR 0.9.0.