In the field of generative syntax, abstractness has a crucial role in how the field is defined and in how it is practiced. This article discusses four ways in which abstractness is essential to progress in the field. First, abstractness is crucial to the formulation of grammars of individual languages. Second, abstractness is intrinsic to one of the goals of the theory, to provide a general theory of language in addition to particular grammars. Third, abstractness plays a role in observations about language, and is therefore an essential part of the empirical validation of the theory. Finally, the paradigm of generative grammar, with its interest in accounting for the linguistic capacity of humans, has increasingly shaped the questions that are investigated and the types of solutions that are considered.