This thesis describes an implementation of a model of natural language grammar based on current theories of transformational grammar, collectively referred to as Government and Binding (GB) theory. A description is presented of the principles of GB, including X-bar syntax and the theories of Case, Theta, Binding, Bounding, and Government The principles, in effect, constitute an embodiment of "universal grammar" (UG), i.e. the abstract characterization of the innately endowed human language faculty. Associated with the principles is a set of parameters that alter the effect of the principles. The "core grammar" of a specific language is an instantiation of UG with the parameters set in a particular way. To demonstrate the cross-linguistic nature of the theory, a subset of the "core grammars" of Spanish and English is implemented, including their parametric values and certain language-specific transformations required to characterize grammatical sentences. Sentences in one language are read in and converted through a series of reverse transformations to a base representation in the target language. To this representation, transformations are applied that produce a set of output sentences. The well-formedness of these sentences is verified by the general principles of UG as controlled by the parameters. Any that fail to meet the conditions are rejected so that only grammatical sentences are displayed. The model is written in the Prolog programming language. / Science, Faculty of / Computer Science, Department of / Graduate