The first Oxford Chromosome Conference, as many will know, was organised by C. D. Darlington and K. R, Lewis and held in the Botany School in July, 1964. Its purpose was to bring together a repres entative international group of those concerned with the study of chromosomes, whatever their organism, methods and objective, in the confident expectation that all would profit by learning about the interests, ideas and discoveries of others whose work might other wise not come to their attention. No similar gathering had been attempted before; because of the wide range of biological cont exts in which chromosome study is relevent, spoken accounts of new research were scattered over many different meetings (and written reports over even more different periodicals). At the time of the first Conference the mechanics of trans mission and recombination were, of course, already well understood in their essential features, although a cloud of mystery still hung over the basis of spindle function and the nature of the centromere. At that time also chromosome study had long been est ablished as a valuable aid to the taxonomist and student of evolu tion on the one hand and the plant breeder on the other. But the new sophistication in the use of biochemical and biophysical methods had only just started to make its impact on our knowledge of chromosome organisation and behaviour.