1. To develop a diagnostic battery sensitive to and specific for the early detection of Alzheimer disease (AD) dementia, the authors reviewed over 400 journal articles dealing with the diagnosis of A.D. or senile dementia and cognitive assessment in organic brain dysfunction and closed head injury. 2. We culled those studies that met our criteria for solid, reliable and statistically significant results and recommend the testing paradigms that most often produced good discrimination of mild AD dementia from normal senescence. 3. These include tests of language, verbal and non-verbal memory, perception, praxis, attention and reasoning. 4. The battery we assembled takes less than 1 hour to administer, requires no special equipment, and was designed as an early screen for use by psychologists, psychiatrists and other trained health care professionals; it is not intended for repeated administration, as in pharmacological or longitudinal studies.