I have no intention of summing up. It would be arrogant for me to tell you which contributions I felt were important. It would be equally pontificating for me to tell you which developments I thought would be important in the future. I did get a little bit worried as the conference went on. I began to think that perhaps the sensors were getting in advance of the users. I mean this not as a compliment to the sensors, but as indicating the kind of situation implied by the title of a conference “Uses of satellites for underdeveloped countries”. Nature referred to this as having an air of “desperate unreality” about it. Radio-astronomy has generally progressed with the sensors ahead of the users, and it has not gone in too bad a way after all. Radio-echo sounding has never been in that state. It has always been dragged forward by the users who were ahead in their requirements. Radar and ERTS imagery are probably the other way round: something in between is probably the best mix.

There has been some reference to the interdisciplinary character of this meeting. I am, I suppose, a bit suspicious of interdisciplinary individuals, but do not imagine by that that I am suspicious of interdisciplinary institutions. They are just what we want, and this conference has been an occasion where people with different specialist interests have been able and willing to talk to one another about what they can do and what they want. That, I think, has been the strength of this conference.