As European Green Capital 2015 and one of the Rockefeller 100 Resilient Cities, Bristol has challenged itself to transform by 2065 into a place where citizens 'flourish' by working together to create wellbeing, and achieve this equitably and sustainably. The Bristol Urban Area can legitimately claim to be in the vanguard of such urban transformation, and yet its development pathway remains characterised by paradox, and the need to deal with some stark realities and to challenge a 'business-as-usual' mind-set if progress towards aspirational goals is to be sustained. This proposal addresses a fundamental issue: what is stopping Bristol from bridging the gap between its current situation and the desired future as encapsulated in the City's various visions and aspirations? We have forged a partnership focused on the contiguous City of Bristol and South Gloucestershire urban area. We have secured the full backing of the two local authorities, Bristol Green Capital Partnership and Bristol Health Partners, the LEP, the local business community, citizen groups, and academics from across both Universities, with tangible commitments of support. Dissolving siloes through partnership, and a genuine interdisciplinary and cross-sectoral collaboration, is core to our approach, and hence both Universities have committed to share equally the financial resources with external partners in a three-way split. It is a key strength of this project that we are able to leverage extensively on internationally leading research assets, including: 'Bristol is Open', the FP7-funded Systems Thinking for Efficient Energy Planning (STEEP), the Horizon 2020 REPLICATE project, ongoing work at the £3.5m EPSRC/ESRC International Centre for Infrastructure Futures (ICIF) and co-produced and co-designed research such as the AHRC/ESRC Connected Communities and Digital Economy funded projects including REACT Hub, Tangible Memories and Productive Margins. We also have access to a wealth of highly valuable data sources including the 2015 State of Bristol Report, Bristol's Quality of Life Survey, and the Avon Longitudinal Study of Parents & Children that has followed the health of 14,500 local families since the 1990s. We intend to build on the ICIF cognitive modelling approach which identifies the importance of challenging established mental models since these entrench a 'business-as-usual' mind-set. At the heart is co-creation and co-production, and an acknowledgement that citizen behaviour and action are essential to the delivery of desired societal outcomes such as wellbeing, equality, health, learning, and carbon neutrality. The work programme synthesises existing domain-specific diagnostic methodologies and tools to create a novel Integrated Diagnostics Framework. We believe strongly that unless an integrating framework is developed to bring together multiple viewpoints, the diagnosis of urban challenges will remain fragmented and understandings will potentially conflict. We will apply this framework in this pilot project to diagnosis complex problems across four 'Challenge Themes': Mobility & Accessibility, Health & Happiness, Equality & Inclusion and the 'Carbon Neutral' city. We have appointed 'Theme Leaders' who are all 'end users' of the diagnostics, ensuring that the process of investigation is cross-sectoral, interdisciplinary, participatory and grounded in real-world context and application. The legacy of the project will be threefold: firstly innovation in the diagnostic framework and methods needed to address urban challenges; secondly its application to the Bristol urban area and the resulting diagnostics synthesise across the four Challenge Themes; and finally the formation of an embryonic cadre of cross-sector city leaders with the capability to apply integrated diagnostics and challenge the prevailing 'business as usual' approaches.