Received: 13 November 2018 Revised: 24 March 2019 Accepted: 26 March 2019 DOI: 10.1111/1467-8500.12383 RESEARCH AND EVALUATION The role of trust in joined-up government activities: Experiences from Health in All Policies in South Australia Toni Delany-Crowe 1 Jennie Popay 2 Angela Lawless 3 Fran Baum 1 Colin MacDougall 1 Helen van Eyk 1 Carmel Williams 4 1 Southgate Institute for Health, Society and Equity, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia 2 Division of Health Research, Lancaster University, Lancaster, UK 3 College of Nursing and Health Sciences, Flinders University, Adelaide, South Australia, Australia 4 Department of Health and Wellbeing, SA Health, Adelaide, South Australia, Australia Correspondence Toni Delany-Crowe, Southgate Institute for Health, Society and Equity, Flinders Univer- sity, GPO Box 2100, Adelaide 5001, South Australia, Australia. Email: toni.delanycrowe@flinders.edu.au Funding information National Health and Medical Research Council, Grant/Award Number: Project 1027561 Abstract Trust has been consistently identified as an important enabling factor for joined-up government activity to gen- erate strong, integrated and effective social policy. Despite this, there has been comparatively little detailed analysis of the complexities and dynamics involved. This paper pro- vides a detailed examination of how trust is built, nurtured and, in some instances, lost during joined-up policy activity. It draws on interview and survey data that reveal the dynam- ics of relationships formed under the South Australian Health in All Policies initiative. The research extends the parameters of organisational analyses of trust. Previous typologies are mostly descriptive, with limited explanatory power, typically focusing on individuals and institutions separately rather than integrating these foci to consider how trust operates within whole systems. By integrating Giddens’ theoretical perspectives on trust with existing typologies, the paper generates understanding about how trust operates as a resource within non-traditional joined- up government working relationships, serving to bridge the gap between the known and unknown, and acting as a productive resource to stimulate action within government systems that are perceived to feature high levels of risk. A model is provided to explain the interrelated dynamics of trust building, maintenance, monitoring and repair. KEYWORDS intersectoral action, policy making, public policy, trust Aust J Publ Admin. 2019;1–19. wileyonlinelibrary.com/journal/aupa © 2019 Institute of Public Administration Australia 1