An intramolecular Ir(III)-catalyzed regio-divergent oxyamination of unactivated alkenes provides valuable gamma-lactams, gamma-lactones and delta-lactams. The regioselectivity is controlled by the electronically tunable cyclopentadienyl Ir(III)-complexes enabling oxyamination via either 5-exo or 6-endo pathways. With respect to the mechanism, we propose a highly reactive [3.1.0] bicycle intermediate derived from Ir(V) nitrene-mediated aziridination to be a key intermediate toward the synthesis of gamma-lactams.