Karla Hartl is founder and chair of the Kapralova Society, a Canadian music society founded in 1998 in Toronto to promote Czech composer Vitezslava Kapralova and other women in music. Hartl's research on Kapralova has been published in Tempo (Cambridge University Press), Journal of the IAWM (International Alliance for Women in Music), VivaVoce (Frau und Musik), Kapralova Society Journal, Czech Music Quarterly, Journal of Czech and Slovak Music, Martinu Revue, Opus musicum, Harmonie, Tydenik Rozhlas, and FOKus. Hartl is co-editor of the first English-language monograph on Kapralova, The Kapralova Companion, published by Lexington Books (Rowman & Littlefield) in the United States in 2011 and shortlisted for the 2011 F.X. Salda Foundation Award. She collaborated on a five-hour radio documentary on Kapralova produced by the BBC Radio 3 for the composer's centenary in 2015, wrote an introductory chapter in another collective monograph on the composer, Vitezslava Kapralova (1915–1940): Zeitbilder, Lebensbilder, Klangbilder, published by Chronos Verlag in Zurich in 2017, and edited a multi-volume collection of Kapralova's correspondence, published by the Kapralova Society from 2015 to 2020. Hartl is the author of Vitezslava Kapralova: Tematicky katalog skladeb a korespondence s nakladateli, published by the Czech Radio Publishing House in 2020, and of Kauza Kaprálová, published by Klic Books in 2021. She is also the co-editor of the Women in Music Anthology, published in 2021 by the Kapralova Society. In 2025, Hartl wrote a script for a five-episode radio series produced by the Czech Radio for the composer’s 110th anniversary, was interviewed for a German film documentary on Czech musical avant-garde, and collaborated on a feature-length Czech documentary on Kapralova.