A varicocele is a common cause of adult male infertility, and surgical ligation is a generally accepted mode of therapy. However, the guidelines for management of the adolescent with a varicocele are not clearly defined. Herein, we describe histologic abnormalities noted on testis biopsy in nine of 24 boys with moderate to large varicoceles. Surgical ligation of the varicocele is recommended when there is volume loss of the testis ipsilateral to the varicocele. All others should be reexamined periodically, and an attempt should be made to obtain a baseline semen analysis.