When Policy Hits Practice–Learning from the Failed Implementation of MST-EA in Australia

Using a qualitative case study design, this study explored why the implementation of Multisystemic Therapy-Emerging Adults (MST-EA), a program for young people with high and complex support needs, failed after a 1-year trial, initiated in New South Wales, Australia. Introducing this novel and complex intervention in parallel with a nation-wide policy reform created considerable implementation barriers, of which the strongest were policy dynamics present in the outer setting of the implementation. Findings highlight the importance of thorough implementation planning, the urgent need to build provider agencies’ implementation capacities and to utilize theories of the policy process in implementation science.