In 1965, Doležel was invited as visiting professor to the University of Michigan in Ann Arbor, where he stayed till 1968. He co-edited (with Richard W. Bailey) a collection of studies "Statistics and Style" (American Elsevier, 1969). On his return to Prague he was appointed research fellow of the Institute of Czech Literature of the Czechoslovak Academy of Sciences, but in the fall of 1968 he left the country after the Soviet invasion of Czechoslovakia. He was invited to the University of Toronto as visiting professor in the Department of Slavic Languages and Literatures, where he later became full professor. He established the study of Czech language and literature at the university. In 1982 he was cross-appointed to the Centre for Comparative Literature. His main research interest was the theory of literature, with a focus on narrative (narratology). Doležel's theoretical position was strongly influenced by analytic philosophy, especially by the conceptual framework of possible worlds. On his retirement in 1988, the Centre organized an international conference "Fictions and Worlds".