Objective: To explore the feasibility and utility of a tolerance break (T-Break) guide on young adults' cannabis use. Participants: Young adults aged 18--29 (n = 125) who were current cannabis users. Methods: Participants recruited through posters and listservs at various universities were offered the T-Break Guide--daily activities, advice, and encouragement--to help complete a 21-day cannabis break. Bivariate analyses examined associations between Guide use and follow-up measures. Results: Compared to non-Guide users, participants who used the Guide "a lot" were more likely to complete the 21-day abstinence break (84% vs. 57%), revise their personal definition of balance to mean less cannabis (84% vs. 62%), and plan a future break (32% vs. 11%). Conclusion: Use of this self-directed T-Break Guide may help young adults take a break from cannabis use and reduce future use. Further research using more rigorous designs to test the Guide's efficacy and assess longer-term maintenance of effects is needed.