This article presents the Alzheimer’s Disease Assessment Scale-Cognitive (ADAS-Cog) for the measurement of disease progression and the patient’s response to drug treatment for Alzheimer’s disease. Previous scales had only limited utility because of low sensitivity and restricted scope. The ADAS-Cog provides more comprehensive and detailed information, meets practical standards and is easy to administer. Special training, however, is needed for administering the test. The scale is designed to measure all the major symtpoms of dementia and determine the increase in the symptom severity; the test is reliable and suitable for the use in a variety of settings. It comprises 11 cognitive items, including spoken language ability, comprehension of spoken language, recall of test instructions, word-finding problems in spontaneous speech, following commands, naming objects and fingers, constructional and ideational praxis, orientation, word-recall and word-recognition tasks. Despite the above mentioned advantages ADAS-Cog cannot replace an extensive neuropsychological test.