Municipal solid waste issue has acquired a growing importance into urban management discussions, particularly in metropolitan areas. Although metropolitan regions were created for integrating public functions of common interest, it appears that the structures, in general, are limited to planning activities. In this context, the democratization process occurred in Brazil during 1980's led to the strengthening of inter-municipal arrangements of voluntary cooperation, acquiring great expressiveness in metropolitan areas, responsible for 60% of waste generated in Brazil. However, despite the consortia emergence as an alternative management of metropolitan territory, its process of setting up and operation is not free of challenges and dilemmas. This paper starts with the hypothesis that inter-municipal consortia in metropolitan areas have high strength asymmetry and weak regional identity among municipalities, conditions that tend to create barriers to its concretization. In this context, this research aims to develop a comparative study of inter-municipal arrangements for solid waste management in the metropolitan areas of Curitiba (pr), Belo Horizonte (bh) and Salvador (ba), by identifying influence degree of regional identity and strength asymmetry in these arrangements. The multiple case study reveals an inverse proportionality relationship between regional identity and strength asymmetry among the municipalities, deeply influenced by political interinstitutional arrangement and the metropolitan area in which they are is inserted. [ABSTRACT FROM AUTHOR]