World models, their progress and applicability

There are now over 30 institutions around the world, where major projects both on world models and world issue modelling are underway. This article summarises some of the general findings about these activities and provides a descriptive account of (a) world dynamic models concerned with the major world subsystems and their interactions; (b) dynamic "issue" models concerned solely with a major sub-system representing a particular world issue or with local problems which have worldwide ramifications; (c) other research programmes relevant to global modelling. The view is taken that although such models may have an important speculative research function, ultimately they are to be of use in aiding policies aimed at the resolution of the urgent world problems they approach.