Cost efficiency in municipal solid waste service delivery. Alternative management forms in relation to local population size Pérez López, Gemma Prior, Diego Zafra-Gómez, José Luis Plata Díaz, Ana María Cost-efficiency municipal solid waste management forms Considerable research has been devoted to the analysis of efficiency and of management forms for mu- nicipal waste collection, but widely varying results have been reported. In this paper, the metafrontier approach, by means of order- m frontiers, is used to analyse the efficiency of different ways of managing waste collection services, in order to determine which form is more appropriate. We compare the results obtained with this approach against those of previous theories. The advantage of applying this methodol- ogy is that unlike traditional nonparametric frontier analysis, we can compare the efficiency of different groups of municipalities according to their population size and to the management form adopted to sup- ply the service. The results obtained suggest that, in general, cooperation formulas are the most suitable for the waste collection service. Thus, intermunicipal cooperation performs best in smaller municipalities (up to 20,0 0 0 inhabitants). However, we find that contracting out the service is associated with higher levels of efficiency in municipalities with more than 20,0 0 0 inhabitants. 2025-05-13T12:15:07Z 2025-05-13T12:15:07Z 2016-12-01 journal article European Journal of Operational Research 255 (2016) 583–592 https://hdl.handle.net/10481/104093 https://doi.org/10.1016/j.ejor.2016.05.034 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional Elsevier