The article focuses on aging's demographic issues, discusses the process of demographic transition. Brazil’s peculiarities in terms of its regional differences and shows the importance of researches which deal with these differences, considering its importance, not only at the country's levei, but also in major Brazilian metropoles. According to the authors, epidemiological studies designed to give information for a more detailed planning for services' organization must be concerned with such facts. The article presents the results of a research, recently in Rio de Janeiro that, instead of analysing the city as a whole, selected, through social, economic and demographic indicators, homogeneous and representative areas of three populational strata. Then it was possible to identify specific problems and distinct demands. Also, it was made a division, according to sex and age group, showing that the distribution of diseases and problems among elderly people hap-pens differently. Emphasis was given to aged women and older people's daily activities.