Dr Gareth Moore is the author of over 200 puzzle and brain-training titles for both children and adults, including The Ordnance Survey Puzzle Book (Trapeze), Enigma: Crack the Code (Michael O'Mara) and The Penguin Book of Puzzles (Michael Joseph). His books have sold in excess of 5 million copies in the UK alone, and have been published in over 35 different languages. He is also a director of the World Puzzle Federation, which oversees the World Puzzle Championships, and a director of the UK Puzzle Association. Find him online at www.DrGarethMoore.com.Dr. Gabrielle M. Finn is Senior Lecturer in Medical Education at Hull York Medical School. She is Director for the Postgraduate courses in Health Professions Education, Education Chair for the Anatomical Society, and Associate Editor for the journals BMC Medical Education and Anatomical Sciences Education.