This chapter focusses on developments in Irish-language prose, drawing attention to innovation in subject matter, literary form and language, and also the persistent and deep-seated anxieties which writers such as Máirtín Ó Cadhain voiced about the future of the Irish language as a creative medium. This chapter considers the context and impact of the language question on Irish-language writing at this time, also examining the emergence of Irish periodicals and independent publishing companies. Ó Cadhain was a particularly prolific publisher in both of these formats, with his 1949 novel Cré na Cille standing out in particular as one of the few internally acclaimed modernist texts that emerged in this era. However, Ó Cadhain was not the only avant-garde writer in Irish, and this chapter also discusses some of the most innovative prose writing to emerge in these decades by non-native speakers of Irish Diarmaid Ó Súilleabháin, Breandán Ó Doibhlin and Eoghan Ó Tuairisc, whose work was collectively characterised by critic Lydia Groszewski as ‘Turgnamhacht na Tríonóide’ (The Experimentalism of the Trinity). It then discusses a generation of new Gaeltacht authors like Siobhán Ní Shúilleabháin, who broke new ground in this period, particularly in their depiction of the social aspirations of young rural women.