This book is an academic scientific book that concentrates on the cryopreservation of human sperm. The book reviews the importance and the current available techniques for sperm cryopreservation. The book also provides the technical details for the application of sperm cryopreservation, and reports an experimental comparison between the conventional slow cryopreservation and the ultra-rapid cryoprotectants- free vitrification, in order to help the decision making regarding the proper technique to be applied in various IVF laboratories. Although this book is a medical scientific one, it is written in a simplified form, in order to allow each couple, interested in the in-vitro- fertilization and or sperm cryopreservation, to inform themselves about the available techniques and the best recommendations.