Ichneumonids are potential biocontrol agents of insect pests and widely used in biological pest control programs in the world. Therefore, this book contains following chapters on Ichneumonids, Prestomerus testaceous, Charops obtusus and Diadegma fenestralis. 1.General introduction 2.Methods of rearing of Ichneumonids and pests 3.Collection, identification and abundance 4.Life cycles 5.Host age selection 6.Host density 7.Intrinsic rates of increase 8.Eco-biology: Temperature, development and survival 9.Ethology: Mating, oviposition and emergence 10.Diapause 11.Methods of biological control. 12.Few research papers. I hope that this is unique book on Ichneumonids and will be useful for farmers, students, teachers, scientists and industrialists.