This book is a comprehensive, practice-oriented guide to the evidentiary regime under the 2015 World Anti-Doping Code (WADC) including the functioning of the Athlete Biological Passport. It is the first to show how the interplay between science and law affects the collection and evaluation of evidence in anti-doping, and how paradigm shifts in anti-doping strategies may modify evidentiary assumptions implicit to the WADC regime. Unique in its dealing with the subtleties of anti-doping science and legal implications, the book gives lawyers involved in anti-doping the keys to a better understanding of the science underlying the WADC regime, while providing anti-doping scientists with the first reference material to understand the legal framework in which their activities are embedded. The emphasis of the book is on international doping cases and it relies predominantly on CAS awards published up to Spring 2015. Written by an experienced Swiss lawyer it provides an insight into the Swiss legal system and its importance for the legal practice in doping matters. Marjolaine Viret is an attorney-at-law in Geneva, Switzerland, specialising in sports and health law. She has gained significant experience in sports arbitration as a senior associate in one of Switzerland's leading law firms. She also holds positions within committees in sport, in particular as a member of the UCI Anti-Doping Commission. Ms Viret had her doctorate on anti-doping approved summa cum laude in 2015. She participates as a researcher in a project for a commentary of the 2015 WADC funded by the National Science Foundation and is regularly invited to lecture or speak in various fields of sports law. The book appears in the ASSER International Sports Law Series, under the editorship of Dr. Dave McArdle, Prof. Dr. Ben Van Rompuy and Marco A. van der harst LL.M.