Dementia is one of the most frequent and disabling health problems of our time. Increased public and professional interest in dementia in the past 20 years, has led to the introduction of better methods of detection and a fuller understanding of the underlying causes. However, diagnostic methods currently available are less likely to be useful in detecting dementia in cases where the initial clinical presentation does not follow a typical pattern of progressive memory loss in later life. This volume provides a fascinating insight into the less common causes of dementia and covers a variety of topics: historical background and classification; uncommon genetic disorders; infections; drugs; neurological and metabolic diseases; autoimmune and endocrinological conditions; toxic and psychiatric illnesses. Together, these papers represent a unique and accessible resource, prepared by a group of experts, for the busy clinician involved in the care of patients who may present via a myriad pathways.