A growing implementation literature outlines broad evidence-based practice implementation principles and pitfalls. Less robust is knowledge about the real-world process by which a state or agency chooses an evidence-based practice to implement and evaluate. Using a major U.S. initiative to reduce long-term foster care as the case, this article describes three major aspects of the evidence-based practice selection process: defining a target population, selecting an evidence-based practice model and purveyor, and tailoring the model to the practice context. Use of implementation science guidelines and lessons learned from a unique private-public-university partnership are discussed.