Georgia Code Title 9. Civil Practice § 9-9-67

(a) Every arbitration pursuant to this article shall be conducted by three arbitrators, one of whom shall be chosen by each of the parties prior to the execution of the submission provided for in Code Section 9-9-65 and one of whom shall be chosen by the arbitrators named in the submission. The third arbitrator shall be chosen after the parties sign the submission provided in Code Section 9-9-65 and before arbitration begins.

(b) If the arbitrators chosen by the parties are unable to agree upon the third arbitrator as provided in subsection (a) of this Code section, the judge authorizing the arbitration and appointing the referee or the judge's successor shall appoint the third arbitrator.

(c) In cases involving a medical malpractice claim where there are multiple plaintiffs or defendants, there shall be only one arbitrator chosen by each side. The plaintiff parties shall have the right to choose one arbitrator and the defendant parties shall have the right to choose one arbitrator.