The human brain is the most complex structure in the known universe. Learning how it works, the relationship between mind and brain, is one of the most fundamental and important of scientific questions and neurobiology one of the fastest growing research areas. New tools, from molecular genetics to the windows into the brain offered by imaging techniques, have transformed our understanding. Brain researchers now claim to be able to explain the roots of human personality and behaviour, of language and even of consciousness itself. Coupled with claims of new knowledge come potential new powers, to cure devastating diseases like Alzheimer's, to control behaviour through tailor-made drugs, to develop human-machine hybrids - cyborgs. But just how far have the neurosciences come in their claims to be able to understand mind and brain? How seriously should we take these new threats and promises? These are the issues that Steven Rose, one of Britain's leading neuroscientists and author of the prize-winning Making of Memory tackles in his major new book. The past, Rose argues, is the key to the present. So understanding the human brain requires that we explore the evolutionary route by which brains emerged, from the origin of life to today's complex societies. And, because the child is parent to the adult, we need to understand how brains develop from a single fertilised egg to the hundred billion nerve cells and hundred trillion connections between them that each human possesses. Against this background Rose asks the challenging question: what does the future hold for the human brain?