work, seems to me to represent somewhat more fairly the contents than does the original symposium title. Given the intent of the symposium, which is expressed in the original title, the published record cannot be expected to be a neatly packaged presentation of some highly defined subject matter. Indeed the diverse subjects represent some, but by no means all, of the varied and dynamic scientific activities that need to be components in the improvement and production of agriculturally Significant plants at a time when world populations are rapidly increasing and shortages of food occurring. In any case, the organizers of the symposium wisely decided that considerations of environment as well as of genetics should be introduced into the thinking of the group and that physiology and molecular biology could not be ignored.