The mission of the Old Church Slavonic Institute is the interdisciplinary research of the Croatian medieval Glagolitic heritage in the Croatian and European context.

Therefore, the scholars of the Institute search for, discover, recognize, record, process and research Croatian and Old Church Slavonic Glagolitic manuscripts, inscriptions and printed books from the perspective of Paleo-Slavic studies, Croatian studies, linguistics, medieval studies, literary history, literary theory, textology, linguistics and the history of the Croatian language, literary theory, textology, lexicography, lexicology, traductology, paleography, codicology, theology, liturgy, biblical studies, classical philology, history, cultural history, art history, history of medicine and information science.

The Old Church Slavonic Institute is dedicated to researching, discovering, recognizing, systematically listing and editing Croatian and Old Church Slavonic Glagolitic manuscripts, inscriptions and printed books.

The Dictionary of the Croatian Redaction of Church Slavonic is being compiled and published as a long-term fundamental project of the Institute, critical editions of Croatian Glagolitic biblical, apocryphal, hagiographical and preaching texts, literary, paleographical and other studies, anthologies, monographs and textbooks.

The grammar of the Croatian Church Slavonic language was also compiled at the Institute. The Institute publishes the international academic journal Slovo and has also launched two new series: Bibliotheca Glagolitica Croatica and the Spomenici Library for critical monographic publications of facsimiles and reprints. The Institute is also the headquarters of the Scientific Center of Excellence for Croatian Glagolitic, where manuscripts from the Istrian town of Berma are researched.

The Institute builds its collections by acquiring scientific and specialized monographs and periodicals, sound recordings of Glagolitic chants, microfilms, photographs, copies and digital recordings of medieval texts, especially Glagolitic texts, whose originals are located in other institutions in Croatia and abroad, in order to bring together in one place the necessary corpus of primary and secondary sources for a credible study of Croatian Glagolitism and the Middle Ages in general.

The digitization of all types of Institute materials is carried out gradually and systematically with the help of modern technology. For the development of all these interdisciplinary scientific researches, for pushing the boundaries of knowledge and the usefulness of this knowledge for others, the most modern scientific methods and computer technologies of research and publication of results are developed. In their college teaching and work on textbooks, the scientists pass on the Institute’s research results to new generations.