Collective decisions and competitive markets

In a general equilibrium model, we allow for households with several, typic ally heterogeneous, members; households that make (efficient) collective co nsumption decisions where different households may use different collective decision mechanisms; yet households that operate within a competitive mark et environment. The interaction of two allocation mechanisms, collective de cisions and competitive markets, is investigated, with a focus on the effic iency properties and decentralization possibilities of the dual allocation mechanism.