This chapter reviews applied research focused on mitigating resurgence, or the relapse of target behavior following a worsening of conditions for alternative behavior. The authors review several mitigation strategies—including reinforcement schedule manipulations, stimulus control, and response-class expansion—that have shown clinical promise. Drawing on both applied and translational work, the chapter underscores the importance of intentional planning for relapse as part of treatment. The authors advocate for a proactive, data-driven approach to behavior change sustainability, particularly related to resurgence.