Martin Rees is a cosmologist and space scientist. He is based in Cambridge, where he has been director of the Institute of Astronomy, a research professor, and (from 2004 to 2012) master of Trinity College. He was president of the Royal Society during 2005–10. In 2005 he was appointed to the UK's House of Lords. He has received many international awards for his research, and belongs to numerous foreign academies, including the US National Academy of Sciences, the Russian Academy and the Pontifical Academy. He is currently on the board of the Princeton Institute for Advanced Study and has served on many bodies connected with education, space research, arms control and international collaboration in science, including the boards of the British Museum, the Science Museum, the Gates (Cambridge) Trust, and IPPR.

He lectures, writes and broadcasts widely for general audiences. His books include Before the Beginning, Our Final Century?, Just Six Numbers, Our Cosmic Habitat, Gravity's Fatal Attraction, and (most recently) From Here to Infinity: Scientific Horizons, an expanded version of his BBC Reith lectures. A further book, 'What we still don't know' is forthcoming.