Scholars have long been interested in new industry emergence, highlighting that it could often be impeded by uncertainty across four dimensions: technology, demand, ecosystem, and institutions. Building on the insight that uncertainty stems from partial knowledge, we develop a conceptual framework that utilizes a temporal and a process perspective for knowledge generation and aggregation. Industry emergence through key milestones—commercialization, firm takeoff, and sales takeoff—is made possible by knowledge-generation processes by diverse actors within and across uncertainty dimensions, and knowledge-aggregation processes with appending, selecting, and collective mechanisms at play. Our conceptual framework integrates across disciplinary perspectives to shed light on both the development of an industry poised for future growth, and the bottlenecks that may delay or even impede industries from emergence.