This study examines the use of strategies and knowledge sources in L2 lexical inferencing and their relationship with inferential success. Data consist of introspective and retrospective think-aloud protocols of 21 intermediate ESL learners who attempted to infer new word meanings from context. Analysis reveals that (a) overall, the rate of success was low even when learners used the strategies and knowledge sources they had at their disposal, (b) different strategies contributed differentially to inferencing success, and (c) success was related more to the quality rather than the quantity of the strategies used. Findings challenge a unidimensional conception of the role of strategies in L2 lexical inferencing and instead support an inferencing model that distinguishes between strategies and the ability to use them appropriately and effectively in conjunction with various sources of knowledge in lexical inferencing. This article discusses the pedagogical as well as theoretical implications of the findings for an integrated model of lexical inferencing. (Contains 6 tables.)