The plaintiffs — registered voters and certain present and former members of the General Assembly — brought this action for injunctive, mandamus, and declaratory relief, challenging the authority of the Governor and Attorney General to enter into a proposed settlement of certain federal litigation concerning the Voting Rights Act, 42 USC § 1971 et seq.1 The trial court concluded that the provisions of *688the proposed settlement were consistent with state law. Hence, it held the governor could settle on those terms. The trial court did not address the issue of ripeness, although that issue was suggested by the state officials. However, we hold that this case is not ripe for review, and remand to the trial court so that it may be dismissed.
The issue presented by the plaintiffs is whether the Governor and Attorney General have the authority to enter into the proposed settlement.2 Our review of the posture of this case and of the federal litigation involved leads us to conclude that, at present, there is no controversy appropriate for judicial determination.
“The existence of an actual controversy is fundamental to a decision on the merits by this court.” Bowers v. Bd. of Regents, 259 Ga. 221 (378 SE2d 460) (1989). A controversy is justiciable when it is definite and concrete, rather than being hypothetical, abstract, academic, or moot. Board of Trustees v. Kenworthy, 253 Ga. 554, 557 (322 SE2d 720) (1984). Similarly, federal courts employ the doctrine of “ripeness” under the Article III requirement of a “case or controversy.” See Wright, Miller & Cooper, Federal Practice & Procedure: Jurisdiction No. 2d, § 3532.
The proposed settlement consists of a three-page “settlement memorandum” jointly from the Attorney General and an attorney for the plaintiffs in the federal litigation, addressed not to the federal judge presiding over any of the federal cases, but to another federal judge, who is serving as a mediator between the parties. The memorandum consists of 16 paragraphs containing specific and aspirational terms concerning the settlement of the federal litigation.
The proposed settlement has been submitted to the federal district court and to the U. S. Department of Justice. However, there is no indication in the record before us that any of the provisions of Federal Rule of Civil Procedure 23 (e),3 which must be met prior to *689settlement of federal class actions, has been satisfied, or that the parties have even begun steps to meet those requirements. What is apparent from the record is that at least some of the plaintiffs in the case before us have intervened in the federal litigation, presumably raising claims similar to those they raise in this case.4
Decided January 29, 1993.
Stanley C. House, Charles L. Wilkinson III, for appellants (case no. S93A0079).
Proctor & Associates, Robert J. Proctor, for appellant (case no. S93A0141).
Michael J. Bowers, Attorney General, Carol A. Cosgrove, Senior Assistant Attorney General, Walbert & Hermann, David F. Walbert, for appellees.
In sum, the plaintiffs challenge a tentative agreement entered into in the federal litigation. In raising these questions, plaintiffs ask this court to do what it is not authorized to do: to render an advisory opinion on hypothetical and legal questions that have not arisen but which appellants fear may arise at a future date. Board of Commrs. of Walton County v. Dept. of Public Health, 229 Ga. 173 (2) (190 SE2d 39) (1972). For the foregoing reasons, we conclude this case is not ripe for judicial review, and the trial court erred by reaching the merits of the case. Accordingly, the trial court’s order is vacated, and the appeal is remanded to the trial court for dismissal.
Judgment vacated and remanded.
Clarke, C. J., Benham, Fletcher, Sears-Collins and Hunstein, JJ., concur.