The use of radioactive luminous paints gives rise to irradiation of luminisers and the public using the luminised articles. Where the public is concerned, radionuclides which do not emit penetrating radiations, such as tritium and promethium-147, are more suitable materials than radium. Experience in the United Kingdom of monitoring luminisers for radium and tritium in their bodies is reviewed and discussed in relation to the possible use of promethium-147. Present conditions in the luminising industry are such that there is a need for regular monitoring of workers and the problems created by tritium and promethium-14.7 are sufficient to restrict their use, probably in favour of radium. There is thus a conflict between what is desirable from the point of view of the public and what is practised by the industry. To resolve this dilemma, it is suggested that the methods employed for luminising should be brought up to much higher standards for containing the radioactive compounds.