This book analyzes the operation of illegal drug markets and explores the implications for prevention policy. Topics include crack distribution and abuse in New York, how young Britons obtain drugs, the impact of heroin prescription in Switzerland, the consumer behaviour of female drug users, heroin use and dealing in an English Asian community, Swedish drug markets and drug policy, performance management indicators and drug enforcement, connecting drug policy and research on drug markets. Contributors to this book are drawn from the UK, Europe and the USA.