Integrity management procedures for thin-walled structures such as gas pipelines are described in this book. This includes various methods for the analysis of crack growth in thin-walled structures and the probability of failure evaluation of pipelines using Monte-Carlo simulation. The practical applications of the boundary element method, finite element method and probabilistic fracture mechanics form a major focus of the book alongside the presentation of the popular methods for SIF calculation and crack growth. The evaluation of failure probabilities based on BS7910 is explained in detail. The procedures described in the book can be used to optimise the maintenance of pipelines and thereby reduce the cost of operating such pipelines. This book will be of interest to pipeline engineers, postgraduate students and university researchers.