Command & Conquer: Red Alert 2 is a 2.5D real-time strategy computer game by Westwood Pacific, which was released for Microsoft Windows on October 23, 2000 as the follow-up to Command & Conquer: Red Alert. Set in the early 1970s, Red Alert 2 supposedly picks up at the conclusion of the Allied campaign of the first game, but this has been subject to debate. Its expansion is Command & Conquer: Yuri's Revenge. Command and Conquer: Red Alert 2 contains 2 playable factions, Soviets and Allies which both previously appeared in Command & Conquer: Red Alert. The single player campaign is structured in an alternate-ending mode as opposed to a progressive story mode.