In this systematic review of weight loss interventions, we reviewed interventions aimed at maintaining weight loss, and identify persuasive elements that drive weight maintenance. Methods: We searched the Medline database for long-term obesity interventions, and targeted randomized control trials that aimed to reduce weight among adults for over 12 months, and extracted outcomes related to body weight change. Results: Seventeen publications were in the final review. Tailoring, or group counseling led by a health care professional, was shown to have a significant effect on long-term weight loss. Positive effects were also obtained by personalization (one-on-one counseling), competition (competing against other people trying to lose weight), and reminders. Conclusion: Maintaining weight loss long-term as so far eluded researchers, but results suggest that that some elements of the interventions are more greatly associated with weight maintenance than others. Future interventions might be more effective if they were based on persuasive technology.