US juvenile justice is at the forefront of experimentation with the evidence-based paradigm, whereby the best available research is utilized to help inform more rational and effective practice. Increasingly, state governments are playing a major role in this endeavor. Maine is one of these states and is the focus of this article. Using a case-study design, we set out to develop a fuller understanding of the events and processes that have contributed to the development, implementation, and sustainment of evidence-based practice in juvenile justice in the state. Four major themes emerged. First, Maine has benefited from strong and lasting leadership within its corrections department. These leaders paved the way for the implementation and sustainment of programs, including finding innovative ways to use existing resources. Second, the adoption of the Risk–Need–Responsivity model was important in laying the groundwork for the use of evidence-based programming. Third, collaborations within and among state agencies and public and private groups were essential. Finally, buy-in and support from multiple stakeholders was and continues to be essential to Maine’s work. Ongoing problems remain with respect to ensuring agencies prioritize fidelity to the model and locating increasingly scarce funding. Implications for other states are discussed.