[en] Comment is made on the recent report on Britain's energy and research programme (the 'Marshal plan') which does not attempt to forecast the future pattern of energy demand and supply in the UK but instead sets out seven scenarios intended to include all the courses which events are likely to take over the next 25 years, and identifies those features which are important in most or all of the scenarios. It is argued that there are four main lines of reasoning against going in with nuclear power in general and the Fast Breeder Reactor (FBR) in particular, in brief, these are whether it can be made safe enough, the disposal of waste, terrorist action, and nuclear war. The Royal Commission on Environmental Pollution, in a recent report, has rejected uncertainty in radiological standards as a fifth line of argument and has recognised that the first four lines are not in themselves grounds for objecting to an FBR development programme. Indeed, this programme might show that the necessary safety standards could not be achieved: if so, we should have to turn to the thorium cycle. (U.K.)