Mental health organisations are expected to identify new best-practice interventions, and find ways to implement them within existing systems and service delivery protocols. This challenging task is further complicated by our interdependencies with other complex service systems, such as education, child protection, and alcohol and other drug services. This presentation will provide an example of one recent strategic implementation of a new mental health intervention. It will describe how multiple services systems were able to work together to stress test a best-practice intervention for infants in proximity to the child protection system, with the goal of identifying and overcoming systemic barriers to the effective implementation of an attachment-based in-home intervention targeting highly vulnerable families.