Development of the convergent lady beetle,Hippodamia convergensGuérin-Méneville, was compared at six constant temperatures. Two populations, one from Corvallis, Oreg., and another from Tucson, Ariz., did not differ in larval survival or developmental rates. Mortality from eclosion of the first instar to adult emergence was 100, 83, 15, 18, 10, and 5% at 13, 17, 21, 25, 29, and 33°C, respectively. Development from oviposition to adult ranged from 51.9 d at 17°C to 11.4 d at 33°C. The heat-unit requirements for development from egg to adult were 228 degree-days above a developmental threshold of 12.5°C. Published data on development ofH. convergensfrom Ithaca, N.Y., and Bushland, Tex., suggest a constancy in developmental requirements for the species from four widely separated regions of North America.