Ventilation/perfusion (VQ) studies have a much wider application range in paediatrics compared with the adult population and provide a noninvasive way to evaluate lung function. VQ studies can be used to determine lung function in patients with primary lung, vascular, cardiac and skeletal pathology. We have examined the literature regarding the current indications of the VQ scan in children. We report a summary of the current indications of VQ scans in paediatrics corroborated by our own experience as a paediatric tertiary referral centre.