[Regional integration of healthcare services in twin cities, Paraná State, Brazil].

This field research aimed to identify healthcare integration among four twin cities in Paraná State, Brazil, the determinants of cross-border movements of foreigners, and the obstacles to such integration. Data were collected through in-depth interviews with key informants that were analyzed with thematic content analysis. The results showed that asymmetries in the structure, resources, supply, and quality of the network's health services are determinants of cross-border movements. The experiences with integration are limited basically to emergency measures in health surveillance. Working groups are formed with limited case-resolution capacity, depending on personal, non-institutionalized initiatives. Public underfinancing is a limiting factor for access to health services. Municipal health services managers play a leading role in border areas, and they should be acknowledged as international political actors.