We constructed a detailed apraxia testing battery consisting of 55 items arranged in seven subparts and applied it to a convenience series of patients with a variety of neurological diseases and asymptomatic control subjects. A total of 173 subjects were evaluated in two culturally diverse settings: Rochester, MN, USA and in Istanbul, Turkey. There was little difference between performance scores in the two sites. The test could be completed within a reasonable time (5-10 min) in cases and in controls in both sites. Patients with Parkinson's disease performed just as well as controls but patients with Alzheimer's disease or other neurodegenerative disorders did less well than control subjects. (C) 1998 Rapid Science Ltd.