9. Discussion and conclusion
By presenting an in-depth case study analysis of the impact of commercialisation on the productivity and performance of the DAA this paper bridges a significant gap in the airport productivity literature, which, to date, has largely employed large cross-country or within-country panel data sets and concentrated on the productivity effects of numerous environmental (e.g. regional competition) and management (e.g. airport ownership) variables, as well as airport characteristics such as airport hub status. While such studies provide valuable insights into the relative efficiency of airports across countries and the determinants of such differences, there is a considerable dearth of in-depth case-study analysis that seeks to get inside the ‘black box’ in the airport productivity literature.