The incidence of resistance in natural populations of the German cockroach (Blallella germanica (L.)) to chlordane and other chlorinated hydrocarbon insecticides has increased since it was first reported in 1953. Some resistance to pyrethrins has been reported, and resistance to malathion has been demonstrated in laboratory-selected strains. Apparently resistance does not exist in other species of cockroaches. Cross resistance has been found to extend within but not between insecticidal groups. Resistance to chlordane or lindane is much more persistent than that to DDT when selection pressure is removed. Laboratory and field evaluation tests have revealed a number of organic phosphate materials that are effective in control of resistant German cockroaches, and mixtures of insecticides that are effective when several species of cockroaches are present. The objectives of some current research programs are briefly stated.