The geochemical context that supported hydrothermal research was also maturing rapidly during the last half of the 20th century. Some observations on that progress may improve our perspective on the advances discussed in the preceding sections of this volume.
Both written and verbal communication among geochemists had advanced remarkably since 1950. The expansion of our field required that major changes came about to improve the ease of interaction. Some stages of that progress are historically pertinent both in the written record of general reference volumes and in a revolution in the organisation of our international meetings.