People with intellectual and/or developmental disability (I/DD) commonly have complex health care needs, but little is known about how their health information is managed in supported accommodation, and across health services providers. This study aimed to describe the current health information infrastructure (i.e., how data and information are collected, stored, communicated, and used) for people with I/DD living in supported accommodation in Australia. It involved a scoping review and synthesis of research, policies, and health documents relevant in this setting. Iterative database and hand searches were conducted across peer-reviewed articles internationally in English and grey literature in Australia (New South Wales) up to September 2015. Data were extracted from the selected relevant literature and analyzed for content themes. Expert stakeholders were consulted to verify the authors' interpretations of the information and content categories. The included 286 sources (peer-reviewed n = 27; grey literature n = 259) reflect that the health information for people with I/DD in supported accommodation is poorly communicated, coordinated and integrated across isolated systems. 'Work-as-imagined' as outlined in policies, does not align with 'work-as-done' in reality. This gap threatens the quality of care and safety of people with I/DD in these settings. The effectiveness of the health information infrastructure and services for people with I/DD can be improved by integrating the information sources and placing people with I/DD and their supporters at the centre of the information exchange process.