Answer:
Both players on the serving doubles team have the opportunity to serve and score points until they commit a fault *(except for the first service sequence of each new game).
The first serve of each side-out is made from the right-hand court.
If a point is scored, the server switches sides and the server initiates the next serve from the left-hand court.
As subsequent points are scored, the server continues switching back and forth until a fault is committed and the first server loses the serve.
When the first server loses the serve the partner then serves from their correct side of the court (except for the first service sequence of the game*).
The second server continues serving until his team commits a fault and loses the serve to the opposing team.
Once the service goes to the opposition (at side out), the first serve is from the right-hand court and both players on that team have the opportunity to serve and score points until their team commits two faults.
In singles the server serves from the right-hand court when his or her score is even and from the left when the score is odd.
Explanation: