Although Ada is now reaching its adolescence, distributed Ada is still in its infancy. The extent of the problems yet to be solved and the multitude of proposed solutions presents a very real dilemma for prospective implementors and users alike. How does one specify a distributed program? What parts of Ada are allowed to be distributed? Will the underlying hardware configuration matter? Can the program be made fault tolerant and reliable in the face of processor failure? How much effort will it take to move an existing Ada program onto a mutiprocessor system? Will the proposed new Ada Standard (Ada 9X) address distributed issues?

These are just some of the questions that arise, and there is considerable effort being expended, world-wide, in answering them. However, much of this work is being conducted in small working groups, and the interim results are published only in condensed form, if at all. The aim of this book is to open the debate to as wide an audience as possible, heightening the level of awareness of the progress that has been made to date, and the issues that still remain open.

The symposium on which this book is based was held at the University of Southampton on 11–12 December 1989 and attended by nearly 100 people.