This article analyses the concepts and phenomena of collaborationism and conformism in Estonia during the Soviet annexation. The focus is on cultural personalities and events connected to choir music and the Song Celebration Movement in 1940-1985. An important source for studying this subject is the correspondence between two creative figures: Tuudur Vettik and Roland Laasmae. This period in the Estonian Song Celebration history was marked by an ideological pressure from the Communist Party, and creative figures--poets, composers, choirmasters and bodies organising the Song Celebrations largely depended on the attitude of party leaders and on cooperation with them to ensure their stable and calm day-to-day existence. Rebels could expect a whole range of repressions: imprisonment, deportation to Siberia, or local persecution and boycott. The article briefly delves into the history of the concept of collaborationism by describing its various nuances and periods; manifestations of the phenomenon are analysed in other fields beside the music. Comparison is made with the history of other West European states (incl. former socialist countries), and the experiences of the Baltic states during the period in question are also analysed. Keywords: collaborationism, conformism, annexation, repressions, deportation, imprisonment, creative intelligentsia, formalism, intellectual fight for freedom, national culture, Estonia, Soviet Union DOI:10.3176/tr.2013.1.01