Book excerpt: Gerhard Mercator (1512–1594) was the most important cartographer and globemaker of the 16th century. He is particularly remembered for his publication Atlas sive Cosmographicae Meditationes de Fabrica Mundi et Fabricati Figura (1595), and for his specific cylindrical map projection (1569), which is still used widely today. This book brings together the latest research on Mercator with a view to his sources and his relationships with other scientific disciplines and cartographers of his time, as well as his role in the wider worlds of Renaissance cartography and Humanism.