This chapter reviews a series of general reactions that hydrofunctionalize electron-neutral alkenes with Markovnikov selectivity through the intermediacy of carbon-centered radicals. This process represents the radical equivalent of Brønsted acid proton transfer. All reactions discussed here involve catalysis by manganese, iron, or cobalt complexes. The scope and limitations of these transformations, along with our current understanding of the mechanism are discussed. The literature is covered up to the end of 2017.