Attrition in youth outpatient mental health clinics ranges from 30 to 70 % and often occurs early in treatment. We implemented specific treatment planning strategies designed to reduce early attrition. Following implementation, 14.3 % of clients dropped out during the first five sessions compared to 26.1 % in the historical control (p < 0.001). During treatment, 33.6 % of clients dropped out in the intervention compared to 55.5 % in the historical control (p < 0.001). Engagement is central to the therapeutic process and may be particularly relevant early in treatment. Implementing evidence-based strategies to promote a collaborative relationship between the family and the clinician may increase engagement and decrease attrition.