The present study identified moderators of Multisystemic Therapy’s (MST) effects on adolescent conduct problems, considering facilitation and proximal process moderation models. The sample included 164 adolescents (mean age = 14.6 years; 83% male) randomly assigned to receive MST or services as usual; parent, youth, and teacher reports of adolescent functioning were obtained. A number of significant moderators were identified. Proximal process moderation patterns were identified (e.g., families with parents with lower levels of adaptive child discipline skills gained more from MST), but the majority of significant interactions showed a facilitation moderation pattern with, for instance, higher levels of adaptive functioning in families and parents appearing to facilitate MST (i.e., greater benefits from MST were found for these families). This facilitation pattern may reflect such families being more capable of and/or more motivated to use the resources provided by MST. It is suggested that factors consistently identified as facilitation moderators may serve as useful foci for MST’s strength-based levers of change approach. Other implications of these findings for individualized treatment also are discussed.