A chiral Koga amine-controlled asymmetric synthesis of cis-gamma-lactones through a formal [3 + 2] cycloaddition of enediolates with a,beta-unsaturated sulfoxonium salts is described. The desired structural motif was formed in moderate to good yields (50-71% for 13 examples), with good to very good diastereoselectivity (dr 5:1 to 10:1 for 20 examples), favoring the cis-isomer, and good to excellent enantioselectivity (70-91% ee for 13 examples).