Design-based implementation research offers the opportunity to rethink the relationships between intervention, research, and situation to better attune research and evaluation to the program development process. Using a heuristic called the intervention development curve, I describe the rough trajectory that programs typically follow as they evolve, and argue that research design considerations and methodological choices are best made in consideration of where interventions are along this curve. Further, I contend that, as programs develop, situational influences play a major role in their evolution and consequently require increased attention to design and methodological considerations. By viewing research as an integral part of a program's development, by making design and methodological choices in consideration of where programs are in their development, and by considering that the situation in which programs evolve as a potential source of change in the nature of the program itself, we alter fundamental perspectives on how research can best contribute to the steady work of building robust programs for educational improvement.