When the time is right: testing for dynamic effects in collaborative performance.

Evaluations of public service collaborations tend to ignore time and timing as potential explanatory variables. Drawing on theories of environmental dynamism, organizational inertia, accountability 'drift', and isomorphism, we test whether the timing of inter-municipal cooperation, and its duration, affect financial performance for solid waste collection inter-municipal partnerships in the Spanish region of Catalonia over the period 2000–2019. Though still present and significant, the cost advantages of cooperation declined over this period due to population growth and reduced interdependence between municipalities. Timing of cooperation has no effect on savings; although early-adopter and follower groups differ in policy objectives. [ABSTRACT FROM AUTHOR]