The advent of nuclear reactors ushered in an era of increasing number of sources of ionizing radiations. However, the potential of ionizing radiations to cause harmful effects was recognized soon after the discovery of x-rays and radioactivityi.e. long before the building of nuclear reactors. Therefore, protection against ionizing radiations has been of paramount concern and has guided the development of atomic energy and related fields. The advances in technology in general resulted in an increase in accidents causing injury and death. It was realised that even medicines, food additives and a host of other substances of daily use had injurious side effects. Smoking was found to be extremely harmful. From these emerged the concepts of quantitative and relative risks. This article discusses briefly the concept of riskvis-a-vis ionizing radiations and approaches to protection against them.