This paper investigates a central place model which possesses much of the simplicity of the Christaller model but which is of considerably greater generality . A prominent feature of the model is the existence of a hierarchy of central places which is based on functional complexity . The model has a number of conceptual advantages over the Christaller model, but also appears to offer a more accurate basis for the description and analysis of actual central place systems.For some time now, central place theory has held the interest of social scientists in a number of fields . It has been used as a framework for finding order and structure within economic landscapes and urban systems, and has also proven valuable as a basis for public policy decisions relating to service provision and the spatial planning of investment (Schultz, 1970 ;Treuner, 1970) . Although central place theory contains much that is conceptually useful, its overall value has been diminished by the fact that theoretical models are frequently incapable of satisfactorily describing and analysing actual central place systems .For example, the `complete-system' model proposed by Losch (1954) is sufficiently complex that it is difficult to test, and the nature of this complexity renders the model inappropriate for many central place systems . By contrast, the central place model developed by Christaller (1966) tends to be highly restrictive in terms of the number of different cases that it can accommodate and, for this reason, is frequently unable to describe actual conditions . Christaller (1950, p . 12) did recognise this deficiency and attempted to modify the original model -an approach which was imaginatively extended by Woldenberg (1968) . Although these modifications improved the descriptive power of the Christaller model, this was only achieved at the cost of increased 35 [Received May 1977] complexity in the spatial structure and in the underlying theoretical reasoning.A rather different approach is followed in this paper . The emphasis will be on exploring a model of the central place system which in several respects is similar to the Christaller model but which does not possess the inherent rigidities of that model . After the model has been outlined and theoretical examples presented, an attempt will be made to provide a rationale for such a model . Consideration will then be given to the possible use of the model in the analysis of actual central place systems .Background