The Croat-Serb Coalition (Serbo-Croatian: Hrvatsko-srpska koalicija/Хрватско-српска коалиција) was a major political alliance in Austria-Hungary during early 20th century that governed the Croatian lands, the crownlands of Croatia-Slavonia and Dalmatia. It represented the political idea of a cooperation of Croats and Serbs in Austria-Hungary for mutual benefit. Its main leaders were, at first Frano Supilo and Svetozar Pribićević, then Pribićević alone.