Hacking and cyber fraud can occur at any time of the day or night, including at weekends and holiday periods. They are of increasing concern to individuals, organisations and Governments and on occasion quick or instant reactions may be required. In many countries, a lot of sensitive and valuable information and important, and at times critical, infrastructure is in the hands of companies. Data theft and denial of service type attacks can have serious consequences for many people. Professor Colin Coulson-Thomas considers the challenges involved in managing cybersecurity.