Friend at Court. Friend at Court is the book of rules and regulations under which tennis is played in the United States. It includes the ITF Rules of Tennis, The Code, and USTA Regulations.It is recommended reading for players, parents, coaches, teachers, tournament directors, league officials and anyone who wants a finer understanding of the game.
https://www.usta.com/en/home/about-usta/who-we-are/national/officiating-rules-and...