In Rios v. State, 186 Md. App. 354, 974 A.2d 366 (2009), the defendant -- Rios -- thought that he had entered into an agreement with the State pursuant to which the prosecution would dismiss all but one of a variety of charges against him, and that as to the remaining count he would enter an Alford plea. When the prosecutor denied the existence of that accord, Rios sought its enforcement in the trial court by filing a motion to seek that relief. The court denied relief, and Rios appealed to challenge the circuit court's order. The Court rejected the State's motion to dismiss Rios's appeal, disagreeing with its position that we lacked jurisdiction because Rios sought review of an interlocutory order. Instead, the Court concluded that Rios's appeal satisfied the collateral order doctrine, which comprises one of "three limited exceptions" to the final judgment rule. Rios, 186 Md. App. at 363. The Court there observed that the order denying enforcement of the plea agreement satisfied the requirements for an appealable collateral order. The Court drew extensively from language in Hudson v. Housing Authority of Baltimore City, 402 Md. 18, 25-26, 935 A.2d 395 (2007), in which the Court of Appeals observed: MThe collateral order doctrine permits a reviewing appellate court to treat as final, without consideration of the procedural posture of a case, a "narrow" class of interlocutory orders in "extraordinary circumstances." . . . We have applied gingerly this doctrine to review actions completely separate from the merits of the litigation based on a "perceived necessity" of immediate appellate review. The collateral order doctrine may apply when a decision of the lower court meets four conjunctive and strictly construed elements. . . . If an interlocutory decision "(1) conclusively determines the disputed question, (2) resolves an important issue, (3) resolves an issue that is completely separate from the merits of the action, and (4) would be effectively unreviewable if the appeal had to await the entry of a final judgment," then the collateral order doctrine applies. In Rios, the Court concluded that the circuit court's decision not to enforce a plea agreement met all of these elements: The State correctly does not contest that the decision meets the first two elements of the doctrine. First, the decision conclusively determined whether the parties entered into a plea agreement, the primary issue on appeal. See Jackson, supra, 358 Md. at 267, 747 A.2d 1199 ("denial of the petitioner's motion to dismiss conclusively determines -- answers -- the question of the enforceability of the agreement between the parties"); Clark, supra, 286 Md. at 213, 406 A.2d 922 ("the order finally resolved the disputed question of whether the plaintiffs were bound by their oral settlement agreement"). Second, this issue is important to the case, as a decision favorable to Rios would result in the dismissal of every charge but one, and obviate the need for trial. See Jackson, supra, 358 Md. at 267, 747 A.2d 1199 (enforceability considered an important issue where judgment for appellant would result in dismissal of all criminal charges). The State does contest, however, whether the third and fourth elements of the collateral order doctrine are met. But the third element is satisfied because the existence of an enforceable plea agreement is an issue independent of appellant's guilt or innocence. See Jackson, supra, 358 Md. at 270, 747 A.2d 1199; Courtney, supra, 98 Md App. at 658, 635 A.2d 8. And the fourth element is satisfied because the existence of a plea agreement is effectively unreviewable after proceeding to trial and verdict, given that an important purpose of making a plea agreement is to avoid the expense, inconvenience, and uncertainty of a trial. The defendant's rights cannot be fully vindicated if he is compelled to wait for a final judgment. See Jackson, supra, 358 Md. at 270-71, 747 A.2d 1199; Clark, supra, 286 Md. at 213, 406 A.2d 922; Courtney, supra, 98 Md. App. at 658-59, 635 A.2d 8. (Rios, 186 Md. App. at 365.) The Court emphasized that the "enforceability of alleged plea agreements is a proper basis for interlocutory appeals because of the strong public policy that favors the plea negotiation process." Rios, 186 Md. App. at 366.