Adopting healthy and positive behaviors and avoiding risky ones are key developmental tasks of adolescence. Parents can play an important role in helping their adolescent children acquire or strengthen the behaviors, skills, attitudes, and motivation that promote physical and mental health and overall well-being. Recognizing this, a variety of programs and interventions engage parents in efforts to achieve one or more outcomes for their adolescents: academic achievement; a reduction in internalizing behaviors such as depression and anxiety, or in disruptive or delinquent behaviors; a reduction or avoidance of substance use; avoidance of sexual risk-taking; and achieving/maintaining health and fitness. In this Fact Sheet, Child Trends synthesizes the findings from 47 rigorous evaluations of parent involvement interventions for adolescents to identify the components and strategies associated with successful programs and interventions. Programs were identified by searching LINKS (Lifecourse Interventions to Nurture Kids Successfully), Child Trends' database of random assignment, intent-to-treat studies of social interventions. The database can be accessed at http://www.childtrends.org/LINKS. We present lessons learned from 47 parent involvement programs that work, don't work, or have mixed results for adolescents ages 12 to 17. Overall, nearly two-thirds of parent involvement programs were found to be effective--30 out of 47 programs had positive impacts on at least one adolescent outcome. Interventions that build parenting skills generally had positive impacts (13 out of 18 worked). All (nine out of nine) family and teen-focused therapeutic interventions were found to work for at least one outcome. On the other hand, parent education programs--those that simply offer information, but do not offer parents opportunities to practice related skills--did not tend to work (only 3 out of 11 had a positive impact). Also, programs with a combined focus on parents and teens--those that include intervention components for both groups--were likely to be effective (21 out of 29 worked). Finally, programs offering at least five sessions were likely to have positive impacts (29 out of 30 such programs worked). Positive impacts for parent involvement programs were least likely to occur for substance use (7 out of 23 programs), educational (one out of seven programs), and reproductive health outcomes (none out of eight programs). (Contains 3 tables.)