This article discusses the relationship between ecological and social sustainability. A large field work was done in the Environmentally Protected Area (Área de Proteção Ambiental -APA) of the municipality of Guaraqueçaba, on the littoral of the State of Paraná, in Brazil, during 1999 to 2001. The research allows us to reach the following conclusions: a) In the interrelation between ecological and social elements, the social aspect determines the ecological aspect. In other words, ecological sustainability is a variable dependent on social sustainability; b) Natural conditions impose relatively important restrictions to economic viability and social sustainability, and; c) Social sustainability cannot be analyzed disregarding the levels of the subsystems contained in the larger system.
social sustainability; ecological sustainability; Environmentally Protected Area (APA)
