This exciting volume brings together the latest work of 26 recognized experts in clinical neuropsychiatry, neuropsychology, neuroscience, and neuroimaging. Part 1 introduces frontal lobe dysfunction. Part 2 delineates the anatomy and neurochemistry of the extended frontal systems underlying neuropsychiatric illnesses such as obsessive-compulsive disorder (OCD) and schizophrenia, details the role of the prefrontal cortex in consciousness and self-awareness, and offers a tantalizing theory on the lateralization of prefrontal cognitive functions. Part 3 focuses on clinical practice. Part 4 covers the role of the frontal lobes in major neuropsychiatric illnesses.