A goal-setting approach was used to examine the way in which 62 patients with closed head injuries or cerebral vascular accidents and 47 orthopedic control patients alter their performance on a four-choice reaction time (RT) task. Both patient groups were randomly assigned to two conditions: one in which a specific and high goal was assigned and one in which a "do your best" goal was given. Statistical analysis indicated that patients with a specific and high goal responded faster than patients with a "do your best" goal. No clinical or neuropsychological variables (e.g., attention, memory) had a moderating influence on the goal setting effect. These results demonstrate that goal setting as a motivational technique is a reliable and robust technique and can enhance performance (intensity of behavior) not only in healthy participants but also in brain-damaged patients.