There is a widespread idea that in grounded theory (GT) research, the researcher has to delay the literature review until the end of the analysis to avoid contamination--a dictum that might turn educational researchers away from GT. Nevertheless, in this article the author (a) problematizes the dictum of delaying a literature review in classic grounded theory, (b) presents arguments for using extant literature in the substantive field within a constructivist grounded theory, and (c) suggests data sensitizing principles in using literature, which are: theoretical agnosticism, theoretical pluralism, theoretical sampling of literature, staying grounded, theoretical playfulness, memoing extant knowledge associations, and constant reflexivity.