Objective: To assess developments over time in the capture, curation and use of quality and safety information in managing hospital services. Setting: Four acute National Health Service hospitals in England. Participants: 111.5 hours of observation of hospital board and directorate meetings, and 72 hours of ward observations. 86 interviews with board level and middle managers and with ward managers and staff. Results: There were substantial improvements in the quantity and quality of data produced for boards and middle managers between 2013 and 2016, starting from a low base. All four hospitals deployed data warehouses, repositories where datasets from otherwise disparate departmental systems could be managed. Three of them deployed real-time ward management systems, which were used extensively by nurses and other staff. Conclusions: The findings, particularly relating to the deployment of real-time ward management systems, are a corrective to the many negative accounts of information technology implementations. The hospital information infrastructures were elements in a wider move, away from a reliance on individual professionals exercising judgements and towards team-based and data-driven approaches to the active management of risks. They were not, though, using their fine-grained data to develop ultrasafe working practices.