Preface. The Testicular Excurrent Duct System: A Historical Outlook; D.W. Hamilton. Evolution of the Vertebrate Epididymis; R.C. Jones. Innervation and Vasculature of the Excurrent Duct System; B.P. Setchell. The Epithelium of the Excurrent Duct System. The Efferent Ductules: Structure and Functions; R.A. Hess. Epididymal Cell Types and their Functions; L. Hermo, B. Robaire. Cellular Interactions and the Blood-Epididymal Barrier; D.G. Cyr, et al. Formation of the Epididymal Fluid Microenvironment; P.Y.D. Wong, et al. Necessity's Potion: Inorganic Ions and Small Organic Molecules in the Epididymal Lumen; T.T. Turner. Protein Secretion in the Epididymus; J.-L. Dacheux, F. Dacheux. Gene Expression and Epididymal Functions; G.A. Cornwall, et al. Specific Gene Expression in the Human and Non-Human Primate Epididymis; C. Kirchhoff. Interactions of the Immune System and the Epididymis; V. Serre, B. Robaire. The Structural Organization and Functions of the Epithelium of the Vas Deferens; L. Hermo, et al. Development and Aging. The Development of the Epididymis; C.M. Rodriguez, et al. Homeobox Genes and the Male Reproductive System; M. Rao, M.F. Wilkinson. Aging of the Epididymis; B. Robaire. Hormonal Regulation and Effects of Toxicants. Androgenic Regulated of the Structure and Functions of the Epididymis; N. Ezer, B. Robaire. The Role of Estrogens in the Endocrine and Paracrine Regulation of the Efferent Ductules, Epididymis and Vas Deferens; R.A. Hess, et al. Retinoids and Epididymal Function; M.-C. Orgebin-Crist, et al. Actions of Toxicants on the Structure and Function of the Epididymis; G.R. Klinefelter. Changes in Spermatozoa During Epididymal Transit.Structural Differentiation of Spermatozoa During Post-Testicular Maturation; G.E. Olson, et al. Changes in Sperm Proteins During Epididymal Maturation; P.S. Cuasnicu, et al. Plasma Membrane Composition and Organisation During Maturation of Spermatozoa in the Epididymis; R. Jones. Acquisition and Development of Sperm Motility upon Maturation in the Epididymis; C.-H. Yeung, T.G. Cooper. Active Oxygen in Spermatozoa During Epididymal Transit; R.J. Aitken. Novel Technological Approaches. Cell and Organ Epididymal Cultures; H.D.M. Moore. Smart Use of Computer-Aided Sperm Analysis (CASA) to Characterize Sperm Motion; S.D. Perreault. Clinical Considerations. Management of Epididymal Dysfunction: Correlation with Basic Physiology; R. Schoysman. The Epididymis as a Target for Male Contraception; T.G. Cooper. Consequences of Obstruction on the Epididymis; C.J. Flickinger, S.S. Howards. Infertility, ICSI and the Epididymis; P. Patrizio, A.-H. Amin. Epididymitis and Other Inflammatory Conditions of the Male Excurrent Ductal System; P.T.K. Chan, P.N. Schlegel. Cancer of the Epididymis; I.J. Okazaki, J.L. Pryor. Author Index.