Radionuclides are used in medicine both for diagnosis and therapy. The radioactive decay data play a key role in the choice of a radionuclide for a certain application. The nuclear reaction data, on the other hand, allow to optimise the production route of a chosen radionuclide. The status of nuclear data of the commonly used diagnostic and therapeutic radionuclides is reviewed and the recent efforts to standardise those data are described. The expected specific activity of the cyclotron produced 99m Tc is briefly discussed. The present efforts are devoted to development of non-standard positron emitters (e.g. 64 Cu, 86 Y, etc.) and low-range highly-ionising therapeutic radionuclides (e.g. 67 Cu, 225 Ac, etc.). The need of intermediate-energy multiple-particle accelerating cyclotrons is pointed out.