Metal-hydride hydrogen atom transfer (MHAT) functionalizes alkenes with predictable branched (Markovnikov) selectivity. The breadth of these transformations has been confined to pi-radical traps; no sp(3) electrophiles have been reported. Here we describe a Mn/Ni dual catalytic system that hydroalkylates unactivated olefins with unactivated alkyl halides, yielding aliphatic quaternary carbons.