Group model building workshops and system dynamics modelling: Taking a Critical Systems approach, conceptual models developed from qualitative data are being used to build and then test, in focus group and workshop settings, the multiple understandings (views) stakeholders have of land use decision-making in urban areas and how these impact on public health. Boundary critique, interdependency mapping and system dynamics modelling are some of the methods and tools being used to understand the problem structure, diagnose challenges and support the design of health improvement interventions.