The main purpose ofthis work is to analyse the relationship existing between reciprocity and moral by studying the main sanitation system, the drinking water supply, the sewerage, the drainage andgarbage collecting in a brasilian suburb. We agree with the hypothesis that the lack ofbasic sanitation and/ or aprecarious system genérate certain way of social exchange related to the system of circulation and distribution ofgoods andservices between people and the household units and to local political actions associatedto some ideas about moral andpoor people justice.