This book provides the essential background theory, information sources, and practical tips that will enable new reconstructionists to start their careers on solid footing, doing work that will withstand scrutiny by judges, juries, clients, other experts, and opposing parties. For practicing reconstructionists, the book presents techniques for gathering information and interpreting evidence, contains computer-based tools for analyzing crashes, and serves as a reference to be consulted throughout their careers, particularly with regard to the underlying physics.