Occupational medicine physicians frequently are presented with requests by employers to determine the work-relatedness of medical illnesses or injuries. Occasionally, this involves a sudden onset of acute epididymitis in the male employee after strenuous activity in the workplace. Because the vast majority of acute epididymitis cases have an underlying sexually transmitted disease component, this poses a real dilemma for the consulting physician. This article discusses the etiology and pathogenesis of acute epididymitis along with its epidemiologic significance and reviews workers' compensation and its possible legal interpretation when acute epididymitis occurs at the worksite.