In biometrics, one of the most important type of physical identification that is based on the personal and unique characteristics of the iris - the colored ring around the pupil of an eye.The whole iris recognition system using Dougman's method is implemented here with the extended implementation of the system with four circle algorithm in iris segmentation stage to make an iris recognition system with efficient use. For efficient iris recognition system we need the best tools in every stage it encountered. This book concentrates on iris localization for that reason. Because if it smooth the way of the segmentation stage for iris recognition, the whole system's output will be successful.