I have wondered about this for a long time: Who or what determines which side of the court the players and the umpire sit on?
—Nancy P. Venie, Woodbridge, VA
While not exactly a rules or regulations issue, there are officiating procedures that cover this. Unless there are overriding considerations (such as a technological issues or a permanently fixed chair), the chair umpire’s back should be towards the sun. So, generally, in the northern hemisphere, any match from midday on should have the chair umpire seated on the west side of the court. The players’ chairs should be flanking the chair umpire. This gives the chair umpire the opportunity to communicate semi-privately with players during changeovers.
Except where noted, answers are based on the ITF Rules of Tennis and USTA's The Code.
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