The material presented in this book is intended to provide the reader with a practical treatment of Weibull distribution as applied to radar systems. Topics include general derivation of Weibull distribution, measurements of Webull-distributed clutter, comparison of Webull distribution with various distributions including Rayleigh, gamma, log-normal and k- distributions, constant false alarm rate (CFAR) detectors for Weibull clutter, non-parametric CFAR detectors, and signal detection in the time and frequency domains. In particular, the Akaike Information Criterion (AIC), which is a rigorously mathematical fit of the hypothetical distribution to the data, is emphasised. This book is written primarily for radar engineers. It is hoped that it will also be of value to teachers and graduate students and of interest to all who are working with Weibull distribution in various fields.