A number of chapters present the most novel research on testicular and epididymal functions or on more general fields of hormone action and molecular cell biology as it is now a tradition. However, exceptionally, the book also contains several chapters dealing with the "Approaches and Tools in the Third Millenium". The unusual inclusion of technologies as such in the 2000 edition of the workshop was an absolute necessity, as these technologies are revolutionizing the fields of biology and medicine and, in many instances, how to do research. This volume gives the scientific community essential information about the very latest technical developments and their potential for future progress.