The high-light of the British Association Meeting at Cardiff was the Symposium on World Food and Population. This was remarkable because the several sections of the Association suspended their separate activities for the day, on September Sth, to assemble in the large Sophia Gardens Pavilion. The proceedings were extremely interesting to all scientists but, as they were not especially concerned with physics, they will only be briefly noted here. Physicists were, however, prominent in the symposium. Sir George Thomson took the chair at the morning session, and Professor P. M. S. Blackett summed up at the close of the afternoon session. It was clear that the members of the B.A. faced up to the fact that the present rate of growth of world population is dangerously large, and that even if tremendous advances take place in the use of land and even if the rate of production of food is enormously increased in the not too distant future, that growth is likely to lead to catastrophe. The position was ably presented in a nutshell by an eminent physicist who, in private conversation, commented that if a nuclear war broke out tomorrow and 200 million people were wiped out, then if the present rate of growth of population persisted, we should be back where we were within five years.