A number of methods exist that allow one to study the pharmacology of neuropeptide release in the airways. Methods include in vitro organ bath techniques to measure neuropeptide release functionally as changes in smooth-muscle tone and direct measurement of neuropeptide release from airway tissue or cultured sensory neurones. The measurement of sensory neuropeptide release from afferent nerves has contributed greatly to our understanding of the role played by these nerves in the control of lung function.