Most airports operate under public ownership, while some are privatized and economically regulated. Only a few airports are privately owned and experience little or no ex-ante regulation of airport charges. On the other hand, airports nowadays earn as much revenue from transport-related activities as from commercially-oriented business activities. Taken together, these two observations lead to a natural question: How to optimally integrate profits derived from commercial activities into the regulation of airport infrastructure charges? This question is addressed in this paper. We discuss basic issues that are relevant for the design of regulatory regimes for airports and how these issues can be tackled by using airport profits derived from commercial activities for infrastructure cost recovery. The main insights are summarized at the end of each section and then are further summarized in the conclusions section.