This article presents a critical overview of research studies which link foreign language aptitude to grammar. It starts by covering fundamental issues--of the structure of aptitude and its measurement. It is argued that the concept of aptitude needs to be updated, and that clear linkages to second language acquisition processes need to be established. The major sections of the article review research on aptitude and pedagogy, and aptitude as relevant to understanding sensitive period effects. With pedagogy, recent articles regarding instructional options and also research linking aptitude to feedback are reviewed. With a sensitive period, the discussion is of aptitude as a potential negator of such an effect, as well as the possibility that aptitude may be linked to second language learning success with younger learners. Suggestions are offered for a reconfiguration of the place of aptitude within second language acquisition.