This cost-effectiveness analysis is based on an implementation-effectiveness study of the Chicago Parent Program (CPP) conducted from 2014 to 2017, in which CPP was implemented naturalistically in 12 Title 1 Pre-Kindergarten (Pre-K) programs in Baltimore City (Bettencourt et al., 2019). CPP is a group-based parenting skills program wherein parents participate in a supportive network with other parents in their child’s community and learn a range of parenting strategies they can tailor to their parenting goals and values (Breitenstein et al., 2020; Gross et al., 2009, 2013). Study participants were parent-child pairs recruited from the Pre-K programs to attend CPP sessions at their child’s school. We sought to estimate the incremental cost-effectiveness ratio (ICER) for CPP’s marginal impact on the prevalence of conduct problems among children at follow-up. By contributing current information about the economic costs and cost-effectiveness of disseminating CPP to all parents in Pre-K programs located in predominantly low-income neighborhoods of U.S. cities, this study may help inform policy discussions of governmental financing to support engagement of families with multiple economic and social disadvantages in U.S. cities. (author abstract)