Without any doubt geography is now in the midst of its third quantitative revolution (cf the statistical revolution in the early 1960s, the mathematical modelling revolution in the early 1970s, and now the neurocomputing revolution in the early 1990s). In common with many other areas of science there is a rapidly growing interest in the application of neurocomputing methods. In many ways the driving force is external to the subject in that the tools are being imported rather than developed indigenously. The new tools are also replacements or complements for, or to, existing methods. The general justification is the promise of an improvement in performance and efficiency, fewer critical assumptions, greater ease in handling hard problems, an expansion of the applicability of quantitative and computer based tools and eventually, automation. It is noted that neurocomputing is just one source of new quantitative tools for geography in the 1990s (Openshaw, 1992a).