This study explores how manners of mediation, and the use of embodiment in interpreter-mediated conversation have an impact on tests of cognitive functioning in a dementia evaluation. By a detailed analysis of video recordings, we show how participants—an occupational therapist, an interpreter, and a patient—use embodied practices to make the tasks of a test of cognitive functioning intelligible, and how participants collaboratively put the instructions of the tasks into practice. We demonstrate that both instructions and instructed actions—and the whole procedure of accomplishing the tasks—are shaped co-operatively by embodied practices of all three participants involved in the test situation. Consequently, the accomplishment of the tasks should be viewed as the outcome of a collaborative achievement of instructed actions, rather than an individual product. The result of the study calls attention to issues concerning interpretations of, and the reliability of interpreter-mediated tests and their bearings for diagnostic procedures in dementia evaluations.