There are global concerns about the proliferation and misuse of club drugs and novel psychoactive substances, yet we know little about their harms and research on clinical management and treatment remains limited. This book fills the knowledge gap by providing a detailed overview of the research evidence available to date. The book provides a framework that allows readers to understand this large number of new drugs, using classifications based on primary psychoactive effect. Within this framework, the book provides detailed reviews of the more commonly used drugs. Each chapter explores pharmacology, patterns and mode of use, acute and chronic harms, and clinical interventions supported by research evidence. An invaluable resource for clinical staff, this book will support clinicians working in the emergency department, substance misuse and addiction services, mental health services, primary care, sexual health services and more. It will also be of interest to academics and those developing drug policy.