This paper is concerned with documenting the contexts in which slip-ups in attempts to stop smoking occur, and of the consequences of the slip-up on the continuation of smoking cessation. A sample of people who had called a Quit Smoking telephone service for information was recontacted three months later. A total of initial 216 slip-up episodes was reported, 44 of which resulted in a resumption of abstinence and 172 which led to relapse. Slip-ups were found to occur in a broad range of contexts, and context was also related to outcome. Slip-ups when in a positive mood, when socializing and drinking alcohol were associated with higher levels of recovery of abstinence, as were those that occurred after more than two weeks of abstinence. Sex differences were also found, with men more likely to slip-up at work, and women to slip-up in a broader variety of contexts.