Empowering consumers to be active decision-makers in their own care is a core tenet of personalized, or precision medicine. Nonetheless, there is a dearth of research on intervention preferences in families seeking interventions for a child with behavior problems. Specifically, the evidence is inconclusive as to whether providing parents with choice of intervention improves child/youth outcomes (i.e., reduces externalizing problems). In this study, 129 families presenting to community mental health clinics for child conduct problems were enrolled in a doubly randomized preference study and initially randomized to choice or no-choice conditions. Families assigned to the choice condition were offered their choice of intervention from among three different formats of the Parent Management Training-Oregon Model/PMTO (group, individual clinic, home based) and services-as-usual (child-focused therapy). Those assigned to the no-choice condition were again randomized, to one of the four intervention conditions. Intent-to-treat analyses revealed partial support for the effect of parental choice on child intervention outcomes. Assignment to the choice condition predicted teacher-reported improved child hyperactivity/inattention outcomes at 6 months post-treatment completion. No main effect of choice on parent reported child outcomes was found. Moderation analyses indicated that among parents who selected PMTO, teacher report of hyperactivity/inattention was significantly improved compared with parents selecting SAU, and compared with those assigned to PMTO within the no-choice condition. Contrary to hypotheses, teacher report of hyperactivity/inattention was also significantly improved for families assigned to SAU within the no-choice condition, indicating that within the no-choice condition, SAU outperformed the parenting interventions. Implications for prevention research are discussed.