Presenteeism describes the situation when workers are on the job but, because of illness, injury, or other conditions, they are not functioning at peak levels. Although much of the research on presenteeism appears in the medical literature, we argue that presenteeism also occurs when employees go to work but spend a portion of the workday engaging in personal business while on the job, such as e-mailing friends, paying personal bills, or making personal appointments. Results of a Web-based survey of 115 individuals suggest that employees spend approximately one hour and twenty minutes in a typical workday engaged in personal activities, costing their employers an average $8,875 each year in lost productivity per employee. Results suggest that engagement in personal business on the job is not related to self-reported measures of performance, efficiency, job satisfaction, organizational commitment, or intentions to stay, only to procrastination. Implications of these findings for practice and research are discussed.