The purpose of this investigation was to determine if setting unrealistic goals would produce any significant decreases in motivation and performance. To add external validity to the findings, two experiments were conducted; one used an endurance task with children, and the other used a basketball-shooting task with college students. Subjects were matched on baseline assessments and randomly assigned to one of several goal-setting conditions—from goals that were easy to those that were unrealistic and virtually impossible. A do-your-best control condition was employed in each experiment. Results from both experiments revealed no significant between-group differences for either the sit-up task or the 3-minute shooting task. Questionnaire results indicated that subjects accepted their goals and tried hard to reach them. Although subjects placed in unrealistic-goal conditions did perceive their goal as being more difficult, this did not produce any decrements in their motivation. Results are discussed in terms of previous research in sport and industrial settings concerning the goal-attainability notion.