Physiologically, the endocrinologic interplay between testes and pituitary gland results in the production of spermatozoa. Before serving their role in fertilizing oocytes, spermatozoa must exit the testis and pass through a complex excurrent ductal system that includes the efferent ductules, epididymis, and vas deferens, which leads to the ejaculatory duct. Pathological conditions in any part of the excurrent ductal system obviously may have a significant effect on spermatozoa transport, resulting in subfertility or infertility. In addition to spermatozoa, semen is composed of secretions from a series of glandular organs, including the prostate, seminal vesicles, the bulbourethral (Cowper) gland and periurethral (Littré) gland. Collectively, these organs are known as the male accessory glands.Various inflammatory conditions, including microbial infection, are by far the most common pathology encountered in the male reproductive system. The term male accessory gland inflammation 1 describes a broad spectrum of inflammatory conditions involving the male accessory glands. The prostate gland and the seminal vesicles together produce about 90% of the ejaculate volume. Although inflammatory conditions of these organs (prostatitis and seminal vesiculitis) are important clinical topics in andrology (Weidner et al, 1998a,b), in this review our discussion will focus mainly on the various inflammatory conditions of the excurrent ductal system. In Part I of this review, our discussion will focus mainly on the various inflammatory conditions of the epididymis and efferent ductile. In Part II, we will discuss the rarely described subject of vasitis and address the management issues and fertility effects of excurrent ductal inflammation.