This chapter comprises 16 case histories that illustrate methods of assessment described in the rest of this book and the use of the Addenbrooke’s Cognitive Examination (ACE)-III. Each case begins with a brief history from the patient and observations by the family followed by findings on cognitive examination focusing on the profile shown on the ACE-III, the results of imaging investigations, and a discussion of the diagnosis and its differential, with a final summary of the principal conclusions, indicating whether the services of a neuropsychologist are required or not. The cases present important common conditions (such as mild cognitive impairment, Alzheimer’s disease in the mild and moderate stages, behavioural variant frontotemporal dementia, progressive non-fluent aphasia, semantic dementia, corticobasal degeneration, progressive supranuclear palsy, and Huntington’s disease) as well as interesting neuropsychological syndromes (such as prosopagnosia, amnestic stoke, and transient epileptic amnesia).