Many groups of biologically important compounds experience cycles of furious research activity and near oblivion. The purines however seem not to be falling into such a pattern. Interest seems to be continuing almost exponentially with no sign of diminution. The result is a frighteningly extensive literature and an increas- ing demand for international conferences and symposia. Unfortunately meetings such as these also spawn increasingly voluminous proceedings and it becomes more and more difficult for a newcomer to the area, or a non- specialist, to obtain the general introductory survey he...