In spite of Michelle Bachelet’s high levels of presidential popularity, and similarly high levels of popular approval for the performance of her government, in late 2009 and early 2010 the Concertación coalition to which she belongs suffered a historic defeat. The result was an alternation in power, reversing 20 years of consecutive Concertación governments. This article analyses the headline social, economic and political events of the electoral campaign that finally produced victory for Sebastian Piñera’s Coalición por el Cambio (Coalition for Change).