This paper seeks to analyze and understand the dynamics of Rio de Janeiro state's population. It does so based on IBGE's 2010 Census results, especially demographic data such as total resident population, geometric average rate of growth, urban and rural population, and population living in the city of Rio de Janeiro. Its starting point is the following questions: How is the population distributed within Rio de Janeiro state's territory? Which comparisons could be made between current Census results and those ones from 2000 Census? Which factors could explain such statistical results? Some relevant traces of instability are visible when it comes to show Rio de Janeiro state's population dynamics. One verifies expressive divergences between the metropolis of Rio de Janeiro and its hinterland, between metropolitan nucleus and periphery, and between urban areas and rural ones, which result in concentration of population. This process stems from differentiated rates of annual growth in some municipalities that privilege the metropolitan nucleus and its periphery throughout the years. According to official criterion adopted by IBGE, this process is reinforced by the massive presence of population in urban areas (towns and cities).
