Are outsourcing and non-aeronautical revenues important drivers in the efficiency of Spanish airports?

This paper evaluates the influence of contracting out, or outsourcing, certain airport services and of commercial diversification strategy. Although most of the effort is being put towards applying non-parametric techniques in airport efficiency studies, we have chosen parametric methodology. We use a distance function, as it has known advantages. The findings show the positive contribution of outsourcing and non-aeronautical revenues on the efficiency of the Spanish airports' network.