This study extends a program of research investigating the effectiveness of Brief Strategic Family Therapy to engage and retain families and/or youth in treatment. The study contrasted Brief Strategic Family Therapy (BSFT) with a Community Comparison (CC) condition selected to represent the common engagement and treatment practices of the community; 104 families were randomly assigned to BSFT or CC. Results indicate that families assigned to BSFT had significantly higher rates of engagement (81% vs. 61%), and retention (71% vs. 42%). BSFT was also more effective than CC in retaining more severe cases. Post hoc analyses of treatment effectiveness suggest that BSFT was able to achieve comparable treatment effects despite retaining more difficult cases. We discuss these results from a public health perspective, and highlight the study's contribution to a small but growing body of literature that suggests the benefits of a family-systems paradigm for engagement and retention in treatment.