This volume is divided into sections highlighting areas of advancement or controversy in the treatment and approach to male factor infertility. The introductory section provides updates on hormonal evaluation and male infertility as well as highlights developments and our current understanding of evaluation of male factor infertility, the assessment of sperm structure and function, and issues related to female fertility. The fundamentals that are required for a urologist to be an effective collaborator with reproductive endocrinologists are also outlined. The second section discusses our understanding of the varicocele, the changing approach of the varicocele, and updates literature regarding the effectiveness of this commonly treated form of male factor infertility. The next section addresses ejaculatory abnormalities. There are many areas of controversy in the therapy of male infertility, and these are reviewed related in terms of medical therapy as well as surgical therapy. Articles devoted to genetic foundations provide the urologist with a genetic primer as well as the essentials required to understand the role of genetic abnormalities in male factor infertility. Finally, information on the effect of aging is also presented, since as our population ages, it happens more frequently that older men are attempting to achieve pregnancies with younger partners.