DDT and BHC were used prior to 1954 as grain protectant but gradually malathion was adopted as prophylactic spray at 50 mg/m2. However, during the continuous usage, doses were enhanced up to 150 mg/m2 to meet the level of effective kill. Toxicity studies on different surfaces, seeds, moisture content level, different insects and stages and emergence of resistance were carried out with respect to malathion and several newer insecticides. DDVP was incorporated in spray schedule at 100 mg/m2. Toxicity data on 17 insecticides, three formulations, persistence on six surfaces and three seeds, tests on 13 insects have been utilized to evolve a strategy for future developments of a prophylactic insecticides. Demerits of switching to new insecticides without broad-based toxicity data have also been advocated. Insects, such as, larva of Trogoderma granarium Everts and adults of Tribolium castaneum (Hbst.), Rhizopertha dominica Fab., Callosobruchus maculatus Fab., Lasioderma serricorne Fab. and Sitophilus oryzae Linn, among beetles and Ephestia cautella (Wlk.) and Corcyra cephalonica Staint from moths were found least susceptible to most of the insecticides. Etrimfos and deltamethrin were adjudged superior for large scale use specially as wettable powder and adjudged suitable to sub-tropical conditions. The paper also provides information on currently used insecticides in India, methods of grain storage at rural and organized level and various constraints faced in the developing countries.