Sjöberg's interest in the cuneiform cultures of the ancient Near East, and especially the languages of Akkadian and Sumerian led him to spend eight semesters between 1953 and 1959 in Heidelberg, where he studied under Adam Falkenstein.
Two years later he succeeded Samuel Noah Kramer as Clark Research Professor in Assyriology, taking over the post as Curator of the Tablet Collections of the University Museum of Archaeology and Anthropology, working alongside his colleagues Barry Eichler and Erle Leichty.
The dictionary project was based on Sjöberg's extensive collection of file cards containing lexicographic information on Sumerian words and expressions, on which he had been working since his days as a student.
[6] Åke Sjöberg's high standards of philological treatments of literary and religious texts, and his lexicographical expertise in Sumerian are widely acknowledged.
Despite his age Sjöberg regularly participated in seminars at Uppsala University, sharing his experiences and knowledge to younger generations of scholars and students.