Government and binding (GB, GBT) is a theory of syntax and a phrase structure grammar (as opposed to a dependency grammar) in the tradition of transformational grammar developed principally by Noam Chomsky in the 1980s. This theory is a radical revision of his earlier theories and was later revised in The Minimalist Program (1995) and several subsequent papers, the latest being Three Factors in Language Design (2005). Although there is a large literature on government and binding theory which is not written by Chomsky, Chomsky's papers have been foundational in setting the research agenda.