The aim of this study was to identify critical health care areas along the Brazilian border. The distribution of health resources was analyzed by municipality and border area in 1999-2000 and subsequently analyzed according to living conditions, health status, geographic accessibility, and other aspects of the border dynamics. Secondary data were used from large national health and geographic databases, complemented by primary data collected in the field. Geographic information systems were used to analyze the data and to produce maps. The border area was heterogeneous in terms of the above-mentioned characteristics. The municipalities along the northern portion of the border strip showed the most unfavorable conditions and thus constitute the most critical area for health care. The central portion showed an intermediate situation, with a balanced proportion of sub-regions in critical versus non-critical situations. The southernmost portion showed a satisfactory situation in all its sub-regions. Health care heterogeneity along the border showed the need for a specific focus, taking the different sub-regions and border dynamics into account.