The present publication has been designed primarily as a textbook for courses dealing with an evaluation of insecticides. It provides a thorough, systematic introduction to the subject as required by the readers. Every effort has been made to keep the book simple and suitable for use as a textbook for the students at undergraduate and postgraduate level. Besides for those individuals not directly involved with the day to day activity of insecticides and pesticides or who have not yet entered a specific field in insecticides and pesticides, this book will be a valuable resource to select from, the many representative approaches available.