The practicalities of obtaining technically acceptable spirometry results with children and young people demand a protocol that follows national guidance and is adjusted to local conditions. Although there is guidance for adults, to date there has been no equivalent for children and young people. The procedural structure should be developed to include consistent standards and values, acknowledgement of contraindications, competence of the testing procedure among clinicians, and constant recalibration and cleaning of equipment. Only if these requirements are met can the results be valid.