An international congress which took two years to plan, embraced a vast range of activities and was attended by some 1400 educators from all parts of the world, could scarcely be satisfactorily described and evaluated within the covers of a single book. Certainly, the provision in printed form of some of the many papers presented at the congress, whilst valuable enough in itself, would convey little impression of the context in which the papers were presented – of the thoughts which prompted them, and of the feelings and reactions they aroused. It was for this reason that the Programme Committee, the committee responsible for planning the professional work of the congress, decided that the official proceedings of congress should attempt to do more than merely present a selection of papers. It should also contain some account of the lengthy preliminary discussions which determined the shape and thus, effectively, the scope of the congress, as well as an attempt to describe the general spirit of the meeting and to identify those themes which arose in the working groups and which could profitably repay further study by individuals and groups before the Third International Congress on Mathematical Education is convened in the summer of 1976.