Nat. Cell Biol. 14, 20–28 (2012); published online 22 December 2011; corrected after print 6 January 2012

In the version of this review initially published online and in print, the key in figure 2 was incorrect. The grey dots should represent Sec23–24, the blue lines should represent Sec13–31 and the green dots should represent TRAPPI. The correct figure is reproduced above, and this error has been corrected in the HTML and PDF versions of the review.