[Si vis pacem, para pacem instead of si vis pacem, para bellum].

In the article the danger of the nuclear war and its possible medical, biological as well as environmental consequences for the population of the whole world have been presented. War is determined by political, social and economic problems, but it need not be the only way of solving complex world conflicts. War is generated in human mind and it is only human mind which can prevent it. The world-wide organization called "International Physicians for the Prevention of Nuclear War" (IPPNW) was set up in 1981 to prove that it is better for the mankind to live in peace than to confront the nuclear peril. In case of the nuclear war health service would not be effective at all and the world's population should have no doubts about it. There is no doubt that the radiologists and other physicians, physicists working on radiation and other technical personnel are particularly responsible for popularizing in the society the knowledge of the basic physical facts and of the medical consequences of nuclear danger.