This chapter provides a critical synopsis of the current state of research on address in Portuguese and Spanish.1 The comparative approach, using two typologically and culturally related languages, provides evidence for the value of contrastive methodologies, especially if grounded in cross-linguistic functions or concepts. The chapter therefore analyses the consequences of the typological discussion of pro-drop languages for addressing, and vice versa. Variation plays a major role in both the synchronic dynamics and the diachronic change of language. In this context, permanent crisis is pointed out as a major property that distinguishes address from other linguistic domains. From a diachronic point of view, a pluralistic approach is proposed that integrates the study of visible diachrony, language elaboration, effects of norms and education, as well as diachronic reconstruction.