Damage caused by Spodoptera exigua, Helicoverpa zea and Heliothis virescens in cotton production is a world wide agricultural problem. In the key cotton growing areas of Mexico, these pests are of primary importance. Data from both experimental and commercial trials have shown that both GemStar (specific vs. Helicoverpa zea and Heliothis virescens) and Spod X (specific vs. Spodoptera exigua) are effective biological control agents for the control of these pests, applied both for early or late control or in an IPM program.