The trajectory of institutional economics changed in the 1970s when new institutional economics (NIE) began to take shape around some relative vague intuitions which eventually developed into powerful conceptual and analytical tools. The emergence of NIE is a success story by many measures: four Nobel laureates in less than 20 years, increasing penetration of mainstream journals, and significant impacts on major policy debates. This rapid acceptance is remarkable when we consider that it was divided from birth into distinct schools of thought. What will be the future of NIE? Will it be quietly absorbed by mainstream theory, or will it radically transform neoclassical economics into a new paradigm that includes institutions? To address these questions, we follow the sometimes-bumpy road to NIE's current successes and ponder the challenges that lie ahead.