Does inter-municipal cooperation (IMC) enhance municipal economic performance? This study employs marginal structural models to address selection into treatment and time-dependent confounding to estimate the effectiveness of IMC in the field of local business development. I use data on municipalities in four West-German states, Lower Saxony, Hesse, Rhineland Palatinate, and Bavaria during the years 2008-2015. I find that, over time, IMC has a positive effect on local economic performance and local business development resources are spent more productively in cooperating municipalities
