We explored the consequences of forming implementation intentions that call for action (adjustment of chosen course of action) versus reflection (assessment of the appropriateness of chosen course of action) in situations that activate people's tendency to remain committed to failing courses of action. In Study 1, when negative experiences preceded failure, action and reflection implementation intention participants showed higher rates of disengagement than mere goal intention and no intention participants. However, when positive experiences preceded failure, only action implementation intention participants maintained this high disengagement rate. In Study 2, we observed that time pressure moderated the facilitating effects of action and reflection implementation intentions on disengagement when negative experiences preceded failure. Whereas the effect of action implementation intentions benefited from time pressure, the effect of reflection implementation intentions did not. The present studies construe disengagement as a self-regulation process and highlight the benefits of implementation intentions as a self-regulation tool. Copyright © 2006 John Wiley & Sons, Ltd.