Financial markets worldwide have been experiencing dramatic changes since the mid-1990s. It has been claimed that XBRL, an XML vocabulary for business reporting, is capable of introducing greater integration and transparency into financial information systems, and thus addressing some of the challenges presented by these changes. This paper presents an exploratory case study of the cooperative design, development and implementation of an XBRL-enabled inter-organisational system (IOS) by the Australian Prudential Regulation Authority (APRA), the Reserve Bank of Australia (central bank) and the Australian Bureau of Statistics to revolutionise reporting by financial institutions in Australia. The study describes how the three agencies modernised and harmonised reporting requirements through a gradual review of the reporting returns required by each agency. This harmonisation enabled the reengineering of the reporting process, as each financial institution now has to submit just one set of figures to meet the needs of all three agencies. The findings illustrate that the complexity of data consumption patterns drove increased interdependence within the financial information supply chain requiring the co-operative development of context sensitive data exchanges and commodity-like IT infrastructures. The paper concludes that the co-operative approach to IOS development exhibited in this study is likely to be more suited to the development of XBRL-enabled systems for financial information supply chains than the ‘hub and spoke’ model characteristic of IOS developments in other industrial sectors.