A resource depletion model of self-control posits that for some period following performance of a task requiring self-control, self-control will be reduced and thus less available for use in a subsequent task. Using 2 substantial data sets collected in real time from individuals who were trying to quit smoking (1,660 and 9,516 temptation episodes collected from 61 and 248 individuals, respectively), we evaluated this model by testing the hypotheses that the number and length of resisted temptations and the intensity of the most recently reported urge during the prior 4 hr predict decreased self-control and increased likelihood of lapsing. Survival and multilevel regression modeling showed that contrary to the hypothesis, the number of recently resisted temptations predicted a lower risk of lapsing in both samples. Duration of resisted temptations had no significant effect in either sample. Intensity of most recently reported urge predicted lapsing in 1 data set but not in the other. Overall, there was little support for the resource depletion model. The protective effect of successfully resisting temptations was an unexpected but provocative finding.