What happens when a functional building is decommissioned? This book investigates liminal spaces: areas we occupy between here and there; structures that exist only as a place to be passed through, rather than as a destination in themselves. Its onus is buildings that have fallen to the wayside, and no longer channel continuous flows of human traffic. Combining architectural insight with a study of the transitory human condition, Airports on Hold analyses a number of obsolete airport infrastructures. As well as exploring how design impacts on an airport's success, this book investigates the relationship between small and medium airports and territories through a series of case studies. The research included herein has been compiled from the author's experiences at numerous universities. Especial thanks go out to the Harvard Graduate School of Design, the University IUAV of Venice, the University of Genoa, and the Universidad Autonoma de Barcelona, for supporting the creation of this book.