This volume contains the papers presented at the NATO Advanced Study Institute on the Interlinking of Computer Networks held between August 28th and September 8th 1978 at Bonas, France. The development of computer networks has proceeded over the last few decades to the point where a number of scientific and commercial networks are firmly established - albeit using different philosophies of design and operation. Many of these networks are serving similar communities having the same basic computer needs and those communities where the computer resources are complementary. Consequently there is now a considerable interest in the possibility of linking computer networks to provide resource sharing over quite wide geographical distances. The purpose of the Institute organisers was to consider the problems that arise when this form of interlinking is attempted. The problems fall into three categories, namely technical problems, compatibility and management. Only within the last few years have the technical problems been understood sufficiently well to enable interlinking to take place. Consequently considerable value was given during the meeting to discussing the compatibility and management problems that require solution before x FOREWORD global interlinking becomes an accepted and cost- effective operation. Existing computer networks were examined in depth and case-histories of their operations were presented by delegates drawn from the international community. The scope and detail of the papers presented should provide a valuable contribution to this emerging field and be useful to Communications Specialists and Managers as well as those concerned with Computer Operations and Development.