Parenting programs aim to motivate change in parents' behaviors, perceptions, and knowledge to promote desirable changes in children's adjustment and behavior. Parenting programs are typically delivered in a group-based or individual format, and it is unknown which format most effectively supports parents. On the one hand, group-based programs may be more effective since they provide access to peer-based support. On the other hand, individual programs may be more successful since they offer a tailored approach. Therefore, this meta-analysis investigated which delivery format is most effective in optimizing child behavior management (i.e., positive reinforcement and nonviolent discipline), parenting stress, and parental depressive symptoms. Studies were selected from the systematic review by Backhaus et al. (2023). Our sample included evaluations of 121 group-based and 41 individual programs based on social learning theory principles. Robust variance estimation indicated that parents' child behavior management and parenting stress improved in both delivery formats. In contrast, parental depressive symptoms improved only in group-based programs. Our findings suggest that whether parents benefit more from a group-based or individual program in part depends on the outcome examined. Therefore, it is important for clinicians to understand parents' goals to effectively guide them toward the most appropriate parenting program delivery format. (PsycInfo Database Record (c) 2024 APA, all rights reserved).