Intensity-modulated radiotherapy (IMRT) is a novel conformal radiotherapy technique which is gaining increasing clinical use worldwide. This article aims to summarize the published data pertaining to clinical indications of this therapy for head and neck, central nervous system, and lung tumours. The main indications in head and neck cancer are parotid gland sparing and dose escalation to tumours close to organs at risk. For central nervous system tumours, IMRT has been used to reduce normal tissue radiation by more conformal dose distributions. To date, the majority of reports concern patients treated in the context of clinical trials, and for most tumour types longer term follow up of treated patients will be required to confirm the clinical benefits of IMRT.