This book reviews how we can record the human brain's response to sounds, and how we can use these recordings to assess hearing. These recordings are used in many different clinical situations - the identification of hearing impairment in newborn infants, the detection of tumors on the auditory nerve, the diagnosis of multiple sclerosis. As well they are used to investigate how the brain is able to hear - how we can attend to particular conversations at a cocktail party and ignore others, how we learn to understand the language we are exposed to, why we have difficulty hearing when we grow old. This book is written by a single author with wide experience in all aspects of these recordings. The content is complete in terms of the essentials. The style is clear - equations are absent and figures are multiple. The intent of the book is to make learning enjoyable and meaningful - allusions are made to fields beyond the ear, and the clinical importance of the phenomena is always considered.