Andrea Calabrese Assuming a set of morphological features in a terminal node of the morpho-syntax, economy requires that they are used maximally. Therefore all of these features must be combined in all possible ways. At the same time, UG principle--probably an instance of the overarching principle of economy governing language--requires that each combination of feature be associated with an exponent. This is a paradigm. Markedness restricts the number of possible combinations, thus giving structure to the paradigm. I will investigate the notion of morphological markedness and provide evidence that many of the structural changes in paradigms leading to identity of exponents are due to featural changes triggered by markedness restrictions.