Abstract: Neuroendocrine tumours comprise a group of neoplasms with variable clinical behaviour. Their growth and spread is often very slow and initially asymptomatic, and thus they are often metastatic at the time of diagnosis and incurable by surgery. An exciting therapeutic strategy for cytoreduction, both for stabilisation of tumour growth and inhibition of hormone production, is the use of targeted radionuclide therapy. Evidence from large-scale, randomised, placebo controlled trials is very difficult to obtain in these rare diseases, but current data appear promising. It is timely to review the principles underlying the use of these therapies, together with the clinical outcomes to date and potential directions for future research.