The GCP Symposium was held in The Hague, The Netherlands, 9-12 October 1978. The Programme as presented at the symposium is appended to this report. The complete compilation of papers has been published as Conference Proceedings CP-258. The technical evaluation for each session has been done partly by the session chairmen and edited by the programme chairman. The evaluation includes most of the comments and recommendations which were received from the particpants in the symposium. (Author).