Sports world is full of arguments. Even before the ball is played, there are questions. Why team A plays team B on Christmas? Why team D travels so much? Almost every fan has complained his or her team had played an unfavorable schedule. It is not easy to answer these questions. The large amount of constraints makes sports league scheduling a very complex problem. In the last thirty years, there has been many researches conducted on this problem. Most of them focus on the time constrained round robin tournament, which is used by many college sports leagues and most professional soccer leagues. There are few researches focus on the time relaxed round robin tournament, which is used by National Basketball Association, National Hockey League, and many amateur leagues. This book is the first ever to systematically investigate time relaxed round robin tournament scheduling problem. It consists of three major parts: the properties of general time-relaxed round robin tournaments; traveling distance problem in the time constrained conditions, all major constraints for the NBA regular season scheduling.