This book draws on research into darknet cryptomarkets to examine themes of cybercrime, cybersecurity, illicit markets and drug use. Cybersecurity is increasingly seen as essential yet it is also a point of contention between citizens, states, non-governmental organisations and private corporations as each grapples with existing and developing technologies. The increased importance of privacy online has sparked concerns about the loss of confidentiality and autonomy in the face of state and corporate surveillance on one hand, and the creation of ungovernable spaces and the facilitation of terrorism and harassment on the other. These differences and disputes highlight the dual nature of the internet: allowing counter-publics to emerge and providing opportunities for state and corporate domination through control of the data infrastructure.