The Levi L. Conant Prize is awarded annually to recognize an outstanding expository paper published in either the Notices of the AMS or the Bulletin of the AMS during the preceding five years. The Conant Prize for 2012 is awarded to Persi Diaconis for his article, “The Markov chain Monte Carlo revolution”; Bulletin Amer. Math. Soc. 46 (2009), no. 2, 179–205.