The rapid rate of growth in 3D modelling in the geosciences has led to an explosion of new models in fields from crystallography to crustal dynamics. However it is suggested in this paper that at present visualisation has developed faster than spatial structuring, and that the range of spatial functions supported is still dominated by the need to view and subjectively “size up” the model. This paper reviews spatial functions in terms of alternative forms of conceptualisation and representation and argues that the next phase of development should be driven by the need to form more sophisticated spatial structurings.