This text explores the concept of major and serious crime investigations as it takes the reader through the fundamental elements of investigative theory and practice that are relevant to this area of criminality. Unlike other texts that concentrate on either bespoke areas of criminality such as homicide, terrorism or tends in concepts such as county lines, this book recognises that the reader will be new to investigative study with little practitioner experience to anchor their learning.By using the latest evidence-based policing knowledge and critical thinking, it explores the concepts of major and serious crime, detailing key areas of legislation and how investigative strategies and decision making can influence successful outcomes.Other topics examined in this text is the key areas of risk for major and serious crime investigations, the impact on investigators, the concept of disclosure, investigative interviewing and how civil orders, designed to tackle this type of criminality can provide a successful alternative to prosecution. Both students and practitioners can find this book useful with this book's contemporary approach of using case studies and contemporary investigative examples relevant to the topic.This book brings together academic theory and operational understanding of major and serious crime that provides learners with an easy to follow guide that they can keep returning to throughout their career.