This new edition comes after about 15 years of development in the field of safety science and practice. The book addresses the question of how to improve risk assessments, investigations, and organizational learning inside companies in order to prevent unwanted occurrences. The book helps the reader in analyzing the subject from different scientific perspectives to demonstrate how they contribute to an overall understanding. It also gives a comprehensive overview of different methods and tools for use in safety practice and helps the reader in analyzing their scope, merits, and shortcomings. The book raises a number of critical issues to be addressed in the improvement process.