Integrated sustainability assessments are being employed by planners to help decision-makers understand the long-term consequences of policy options. This paper describes an urban sustainability assessment framework first presented at SOAC 2011 and explores its use with practitioners on a real-world case study in Logan City, Queensland. The framework includes four stages, namely scoping; visioning; experimenting and assessment and includes the use of system condition indicators, agent-based modelling and multi-criteria assessment. The framework uses formal methods to ensure that system understanding and description, policy design and policy outcome evaluation and assessment are well-coordinated with each other, each deliberatively informing the others as they all co-evolve. The focus of the paper is on how such frameworks may be applied in Australian planning practice, using results from workshops held with Logan practitioners in 2014/15. Key results include how the framework and its outputs are perceived by planning actors. Findings suggest that system analysis, timely identification of stakeholder’s interests, the use of appropriate evaluation criteria, communication of modelling results and formal assessment all remain important. Tensions between the perceived rationality of the framework and how it connects with decision-making remain. But perhaps the most significant finding is the use of the framework in framing the integration problem by responding to five integrative functions: descriptive, evaluative, strategic, contextual and mutual.