The Oxford Handbook of Synesthesia brings together this broad body of knowledge into one definitive state-of-the-art handbook. It includes a large number of concisely written chapters, under broader headings, which tackle questions about the origins of synesthesia, its neurological basis, its links with language and numbers, attention and perception, and with 'normal' sensory and linguistic processing. It asks questions about synesthesia's role in language evolution, and presents both contemporary and historical overviews of the field. It shows synaesthesia's costs and benefits (e.g., in creativity, memory, imagery) and describes how synaesthesia can provide inspiration for artists and designers. The book ends with a series of perspectives on synesthesia, including a first-hand account, and philosophical viewpoints which show how synaesthesia poses unique questions about sensation, consciousness and the nature of reality.