His most important contribution is in comparative literary studies and translation studies in particular. Drawing upon the notions of polysystem theorists like Itamar Even-Zohar, he theorized translation as a form of rewriting produced and read with a set of ideological and political constraints within the target language cultural system. Lefevere developed the idea of translation as a form of rewriting, which means that any text produced on the basis of another has the intention of adapting that other text to a certain ideology or to a certain poetics, and usually to both.
Lefevere, along with Gideon Toury, James Holmes and Jose Lambert, can be considered among the foremost scholars who have made translation studies an autonomous discipline. Together with Susan Bassnett he envisaged that "neither the word, nor the text, but the culture becomes the operational ‘unit’ of translation". This has been hailed by Edwin Gentzler, one of the leading synthesizers of translation theory, as the "real breakthrough for the field of translation studies"; it epitomized what is termed "the coming of age" of the discipline; an increasing intercultural or multicultural trend, that might be termed the postcolonial turn.