The simultaneous elucidation of “mobility” as a regular circulation of individuals or groups between Maya cities, and of the “migrations” that apparently took place during the Terminal Classic across the Maya Lowlands is key to our understanding of the transition (collapse or crisis) from Classic to Postclassic societies. How regular mobility related to social and economic practices during Classic times may help predict posterior, larger movements like the abandonment of Classic cities and the urbanization of Postclassic cities? Evaluating (in rhythm and size) the development of residential masonry architecture within Classic urban neighborhoods allows the archaeologist to outline specific social dynamics over time that determined forms of immigration and emigration of households and/or entire groups. Case studies from a number of Lowland sites are presented to illustrate and contextualize series of movements that would have paved the way for massive or non massive, rapid or gradual abandonments of urban neighborhoods under specific historical circumstances.