A renaissance in the astrophysics of massive stars is currently underway, driven by asteroseismology, supernovae, and gravitational wave observations. I will discuss several processes that occur at the end of massive stars’ lives that influence their supernovae and compact remnants. I will present a new model for mass loss from red supergiants via dense chromsopheric material supported by shock waves emanating from the stellar surface. This dense chromosphere may account for the puzzling circumstellar material inferred from early observations of many type II-P supernovae. Low-mass helium star supernova progenitors expand rapidly at the end of their lives, which can drive intense mass loss in the presence of a binary companion, and may be able to account for many type Ibn supernovae. High-mass helium stars collapse into black holes, and I will discuss new calculations of their tidal spin-up that predict lower black holes spins than most prior work.