This coordinated project has as goal a comparative study of the grammatical variation given in the Romance languages, Spanish and Catalan in particular. "Microvariation: syntactic and morphonological aspects of the object languages. It attempts to characterize the primitives responsible for the microvariation and to identify a possible inventory for them. In the morphosyntactic domain, we will study the properties and geometry of formal features (...) In the morphonological domain, we will pay particular attention to teh relation between the formal feature structure and its realization (allomorphy, defectivity) (...)