Cyber-security is headline news and a growing challenge for national and global security, while computer technology now pervades every aspect of the personal and professional lives of our graduates. This technology underpins enormous performance improvements but also brings serious vulnerabilities. The many forms of cyber-threats - such as data theft, surveillance, and system compromise - have become tools of activism, corporate and state espionage, warfare, counter-proliferation, and intelligence gathering. This course provides an in-depth introduction to the strategic and national security challenges of cybersecurity, and provides students with the skills to defend their organisation and their personal computers from the most common forms of attack.