Objective: To review the studies that test treatments targeting adolescent suicidal ideation, suicide attempts, or self-harm, and to make recommendations for future intervention development. Method: The extant randomized clinical trials that aim to reduce the intensity of suicidal ideation or the recurrence of suicide attempts or self-harm were reviewed with respect to treatment components, comparison treatments, sample composition, and outcomes. Results: The majority of studies that showed any effect on suicidal ideation, attempts, or self-harm had some focus on family interactions or nonfamilial sources of support. Two of the most efficacious interventions also provided the greatest number of sessions. Some other treatment elements associated with positive effects include addressing motivation for treatment and having explicit plans for integrating the experimental treatment with treatment as usual. In many studies, suicidal events tend to occur very early in the course of treatment prior to when an effective "dose" of treatment could be delivered. Important factors that might mitigate suicidal risk, such as sobriety, healthy sleep, and promotion of positive affect, were not addressed in most studies. Conclusion: Interventions that can front-load treatment shortly after the suicidal crisis, for example, while adolescent suicide attempters are hospitalized, may avert early suicidal events. Treatments that focus on the augmentation of protective factors, such as parent support and positive affect, as well as the promotion of sobriety and healthy sleep, may be beneficial with regard to the prevention of recurrent suicidal ideation, attempts, or self-harm in adolescents.