The first enantioselective Neberreaction of β-ketoxime sulfonates catalyzed by a bifunctional thiourea has been developed. The reaction proceeds stereoselectively with 5 mol % of the catalyst to give the 2H-azirinecarboxylicesters in good yields with up to 93% ee. In addition, the resulting azirines can be successfully employed in the stereoselective synthesis of di- and trisubstituted aziridines