Airports and urban developments in their vicinity constitute a highly specialized type of agglomeration based on air connectivity that epitomizes the importance of mobility in the modern service economy. However, in a frictionless world of backyard capitalism and perfect competition, such agglomeration of civil aviation services would not have been necessary. Thus, concepts such as imperfect markets, path dependence, and cumulative causation may be alternatively used to explain the spatial aspects of airport developments. Focusing on “second-nature” concentration, the “new geographical economics” (NGE) literature offers a potential theoretical framework that organizes these concepts into a coherent economic framework. This chapter aims to highlight the unique relevance of the NGE approach in developing an economics-based understanding of the spatial distribution of airports. Drawing from the existing NGE knowledge-base, this conceptual chapter explains that the NGE approach can be adopted as a micro-foundation to show how the spatial aspects of airport development, including core-periphery dynamics of regional disparity and parity, can emerge from economic mechanisms. The chapter concludes with potential implications for airport economics and regional policy, along with the discussion of some of the main critiques of the theory.