Like a phantom, "gene doping" has been haunting the debates on the future of competitive sport for years. Such fantasies and visions often culminate in the image of super athletes whose genetic make-up has been permanently manipulated. But the expected application scenarios will be much more unspectacular, but at the same time more probable and closer. We will soon have to reckon with the use of new substances as well as gene and cell therapeutic methods for the targeted manipulation of gene activity. Their use promises highly efficient performance enhancement and will be difficult, if not impossible, to detect. This volume provides comprehensive answers to the key questions of further development: What scientific results could be used for possible gene doping, where will the gateways be in elite and popular sport, and how can we react to this with the help of prohibition and control structures? It is also asked which individual behavioural patterns of athletes and which social contexts will play a role in the expected career of gene doping.