Thi s book ari ses from The Fourth European Coll oqui urn on Theoret i ca 1 and Quant itat i ve Geography wh i ch was he 1 din Ve 1 dhoven, The Netherlands in September 1985. It contains a series of papers on spatial choice dynamics and dynamical spatial systems which were presented at the colloquium, together with a few other soll icited ones. The book is intended primarily as a state-of-the art review of mainly European research on these two fastly growing problem areas. As a consequence of this decision, the book contains a selection of papers that differs in terms of focus, level of sophistication and conceptual background. Evidently, the dissimination of ideas and computer software is a time-related phenomenon, which in the European context is amplified by differences in language, the profile of geography and the formal training of geographers. The book reflects such differences. It would have been impossible to produce this book without the support of the various European study groups on theoretical and quantitative geography. Without their help the meetings from which this volumes originates would not have been held in the first place. We are also indebted to the Royal Dutch Academy of Science for partly funding the colloquium, and to SISWO and TNOjPSC for providing general support in the organisation of the conference.

Conventional methods and models for spatial data analysis are based on 'hard' (quantitative, cardinally-measured) information. Approaches such as location-allocation models, optimization models, entropy models, spatial assignment models and regional growth models all re flect the past trend to cast complex and multidimensional spatial interaction patterns in the framework of a cardinal metric system. In recent years, significant progress has been made in the analysis of 'soft', qualitative or categoricaily-measured data. In the fields of both parametric and non-parametric statistics and econometrics, a wide variety of techniques and models have been designed which treat qualitative variables in an appropriate manner. All these methods and techniques aim at taking into account the limitations caused by measuring variables on a non-metric scale, and try to avoid he use of non-permissible numerical operations on qualitative variables. These endeavors have resulted in new catch phrases for the analysis of qualitative data, such as 'soft econometrics', etc. Researchers in the areas of regional and urban economics, geography and planning have become increasingly aware of the necessity to in corporate qualitative data and a wide array of methods for quali tative data are now being applied. Applications have included, for instance, spatial consumer choice behavior, locational perceptions and preferences, contingency table analysis, spatial scenario analysis, qualitative impact analysis, project and plan evaluations, spatial conflict analysis, and so forth."