We would like to thank Professor John Hutchinson for his contribution of a discussion to our paper and we would like to respond to the comments he raises. The focus of our paper was on the development of new techniques to display, visualise and attribute 3D geological models in urban areas, in this case the Thames Gateway Development Zone in London. The production of such models does indeed require the collation, data-basing and interpretation of large numbers of good quality site investigation boreholes. 3D geological models are then constructed by experienced geologists who are specialists in the geology being studied. Once constructed, the modelled lithostratigraphic units can then be attributed for a number of different characteristics, such as strength, plasticity and porosity. The 3D attributed geological model is not designed with a specific engineering project in mind; instead it should be viewed more as a desk study resource. For example, the 3D attributed model developed for the Thames Gateway Development Zone provides a way of presenting geo-environmental information in a more accessible and understandable form to the wide range of data users working within the Thames Gateway region. Although urban areas are intensively investigated, unforeseen ground conditions are still a major cause of project overspend. One of the reasons for this is that geoenvironmental data is not always readily accessible, as it is held, in the UK, by numerous clients, consultants, and local authorities. There is, therefore, a need for geologists and engineering geologists alike to be able to visualise ground investigation data from a variety of different sources. BGS is working to collect and data-base this wide range of geoscience information, including site investigation data. This information is now being used to produce attributed 3D models such as those described for the Thames Gateway (Royse et al. 2009). Used correctly, these models should reduce ‘‘anomalous ground conditions’’ that still plague developers (De Freitas and Royse 2009). The authors acknowledge the importance of the total engineering approach as advocated by Fookes (1997), Fookes et al. (2000) and Baynes et al. (2005). The total engineering approach is particularly helpful where there is little useful 3D ground information. Baynes et al. (2005) advocate geological and geomorphological mapping of a route corridor early on in the development process, because it is inexpensive when compared to subsurface investigations and more likely to provide relevant information no matter what direction the final configuration takes. However, Baynes et al. (2005) also say that a high level of geological and geomorphological comprehension is not in itself enough. In essence, the value of geological information is not in the possession of it, but in the interpretation and presentation of that data to those that need it most. Furthermore, the delivery format must make the data more accessible, relevant and understandable. In urban areas, the 3D model could be used as a part of the total engineering approach for specific engineering projects. The attributed geological model, in essence, provides a platform from which a variety of data sources such as geological, hydrogeological and geotechnical information may be integrated and visualised together, thereby enabling those engaged in large-scale construction and regeneration projects to access environmental geoscience information. The models inform specialists and non-specialists alike, so they are able to make appropriate judgements and decisions. K. R. Royse (&) D. C. Entwisle British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham, UK e-mail: krro@bgs.ac.uk