Gravitational wave detections are revolutionizing our knowledge of the stellar mass black hole population. Gaia is unveiling a new population of dormant black holes in detached binaries with stellar companions. Microlensing probes isolated black holes that are otherwise unobservable. Time domain surveys are searching for transients marking the birth of black holes or their interactions with their stellar companion. Together, these detections are revealing a new population that complements the accreting black holes long known from X-ray and radio surveys.

These new data compel us to assess our understanding of the lifecycle of stellar black holes: the complicated lives of their massive star progenitors, the collapse of their cores and the associated transients, their afterlives as dormant or accreting black holes, and their possible finale as gravitational wave sources when they merge. We will bring together a broad community to review the most recent findings, and develop new observational and theoretical strategies to answer urgent questions on the lifecycle of stellar black holes.