Sustainable decision making in Urban Design is a complex and non-linear process that requires the interaction of a wide variety of stakeholders. The engagement of a range of stakeholders throughout the decision making process presents challenges including the need to communicate the complex and interdependent facets of sustainability and the need to demonstrate the short and long term implications of alternative courses of action.This paper presents the results of an initial application of a prototype simulation and visualisation tool (S-City VT) that was developed to enable all stakeholders, regardless of background or experience, to understand, interact with and influence decisions made on the sustainability of urban design. S-City VT takes the unique approach of combining computer game technology with computer modelling to present stakeholders with an interactive virtual development. The paper uses the Dundee Central Waterfront Development Project as a case study to evaluate the potential for the application of the tool and explains how parallel research work on the implementation of a sustainability enhancement framework for the Central Waterfront Development has informed the choice of sustainability indictors and identified the key stakeholders in the decision making processes.The paper shows how stakeholders can be presented with the outputs from the model using a 3D visualisation of the development and thus enables judgements to be made on the relative sustainability of aspects of the development. The visualisation tool employs a number of different methods of displaying the sustainability results to the stakeholders. These methods can show data in varying levels of complexity, depending on the expertise of the stakeholder, empowering all stakeholders by illustrating possible interactions between indicator values and sustainability and by showing how different stakeholder perceptions of the importance of the indicators can influence the sustainability assessment.Initial tests on the effectiveness of the different visualisation methods in displaying the model output to communicate the sustainability of the Development are described. The results of the tests and presented and discussed and conclusions are drawn on the further development and application of the tool to model and visualise through time the possible results of decisions made at different stages of the project
