How do serving, receiving and the order of play work in doubles?

The serve (Law 2.6.3): the ball must bounce on the server's right half-court, then on the receiver's right half-court (diagonally). The centre line counts as part of each right half-court, so a serve on the centre line is good.

Hitting order (Law 2.8.2): server, receiver, server's partner, receiver's partner, and so on. Partners must alternate shots; hitting out of turn loses the point.

Who serves and receives (Law 2.13):

• In each game, the pair serving first chooses which of them serves first. In the first game, the receiving pair chooses who receives first.
• In later games, once the first server is chosen, the first receiver is the player who served to them in the previous game.
• At each change of service, the previous receiver becomes the server, and the partner of the previous server becomes the receiver.
• In the last possible game, the pair due to receive next swap their receiving order when one pair first reaches 5 points.