One far-reaching goal of linguistic theory is to determine universal principles which hold for the structures of all human languages.1 Such principles are proposed as part of a system of UNIVERSAL GRAMMAR (UG), which is claimed to be part of the biological endowment for all human beings. Thus, these principles must be general and abstract enough so that a child learning his or her native language — whatever that language might be — will unconsciously use them, along with the primary language input data, to guide the formation of a grammar for his or her own particular language. Since there is great variety in the form of the world’s languages, it has been proposed that the universal principles are supplemented by language-particular parameters, which allow for a limited and specific set of options within the confines of the universal principles (e.g., Chomsky 1981, Hornstein and Lightfoot 1981, Lightfoot 1982, Newmeyer 1983, Roeper and Williams 1987).