The phenomenon of insight is frequently characterized by the experience of a sudden and certain solution. Anecdotal accounts suggest that insight frequently occurs after the problem solver has taken some time away from the problem (i.e., incubation). However, the mechanism by which incubation may facilitate insight problem-solving remains unclear. Here, we used compound remote associates problems to explore the likely mechanisms by which incubation may facilitate problem-solving. First, we manipulated problem fixation to explore whether forgetting can explain incubation effects. Second, leveraging previous work linking the experience of insight to unconscious semantic integration, we asked participants to report their experience of insight after each problem solution, including problems solved after a period of distracted incubation. We hypothesized that incubation was not principally important for forgetting but rather frequently causes a shift to a more unconscious semantic integration strategy. Consistent with this we found that initial problem fixation did not predict the improvement in problem-solving after incubation and that participants were more likely to report insight on problems solved after incubation. Our findings suggest that incubation may facilitate insight problem-solving leading to a mind-set shift to a more unconscious problem-solving strategy involving semantic integration.