Helping youth with serious mental health conditions transition from adolescence to adulthood has also meant transitioning them from child to adult mental health services, which are two very different systems. One’s age (e.g., 18, 21, or 25) often serves as the criteria that divides eligibility for one provider or system of service to another. The consequence of this practice is that mental health services are typically oriented to children or young teens or to mature adults, but are not tailored to the “between” ages of 14 – 25. Despite this discouraging scenario, there are mental health programs that succeed in serving youth and young adults across the “between” age without discontinuity of services. We researched these programs to learn about the processes they used to establish such services in 2006. “Pioneering programs” that continuously serve people from adolescence through early adulthood (typically 16-23) were identified. Administrators, program staff and other stakeholders from seven programs across the country that are partly publicly funded were interviewed using a standard set of questions. We wanted to find out how these transition programs came about. Additionally, we identified one state and one federal pioneering grant program that we included in this report. A Spanish translation of this publication is available for download. Originally published as: Research You Can Use, Issue 2, 2011. Also issued as Transitions RTC Research Brief 1, Feb. 2011.