The New GUI for Mac OS X Simon Urbanek and Stefano Iacus In R 2.0 we have introduced a new GUI for Mac OS X which takes advantage of many new features of the Cocoa toolkit that comes with the Mac OS X operating system. We have added several improvements in the meantime and released a much extended version with R 2.1. In this talk we discuss many? features and additions that are available to Mac users in this GUI.