Data on insecticides for mid- and late-season insect control in cotton were evaluated at Stoneville, Mississippi, for 1961-84. Data from these evaluations provided information on yield response attributable to controlling mid- and late-season tests in cotton. Yields from untreated checks and from the treated tests were harvested and determined. Prices for the insecticide in the year of the study were used in this evaluation as well as application costs for that year. Average prices received by farmers in Mississippi for cotton and cottonseed for each year of the study were used to determine increased value due to insect control. Different insecticides gave different levels of control in terms of returns above control costs in different years. Various groups of insecticides over time gave different returns for the years in which they were tested. Pyrethroids have resulted in the greatest returns above costs of any group of insecticides used in this study.