Few studies have tested potential explanatory mechanisms for the high stability of extraversion. In this study, the relationship between extraversion, appearance evaluation, and cosmetic surgery was investigated to examine such mechanisms. The ‘‘Big Five” personality traits were assessed in 155 female cosmetic surgery patients prior to and 6 months after surgery, as well as from a representative sample of 907 women. Patients showed higher extraversion scores prior to surgery than were found in the representative sample; further, extraversion scores increased after surgery, while the increase diminished when controlled for appearance evaluation. The results are in accordance with a transactional model, whereby extraverts engage in actions that reinforce extravert tendencies, which may account for the high stability of extraversion. 2009 Elsevier Inc. All rights reserved.