During the 20th century, technologies developed at a rate never previously witnessed. It is likely that the 21st century will witness even more radical change. Examples of areas where future technologies may have a major influence include the biological conditions affecting human physical, cognitive and affective capacities, synthetic biology, robotics and artificial intelligence, nanotechnology, advanced surveillance techniques and geotechnologies. In this theme, two central questions that will be addressed are (1) Which areas of research in the natural sciences, technology and medicine should be prioritised in order to avoid the worst outcomes? and (2) How can we best understand and analyse technological risk, and how can we apply existing tools from other research areas, such as risk management and scenario planning, to increase our understanding of how we should weigh potential risks against potential opportunities?