Many factors and pressures affect decisions made in UK university libraries on opening hours especially 24/7. This article reports on a project to examine the decision-making process, influential factors, and stakeholders. A workshop for senior library managers in the East Midlands was held to gather data and share experiences. From analysis of the workshop a framework of influential factors was devised and the decision-making process was examined. Although each library had different priorities, important factors overall included pressure from undergraduates and the student's union, and provision during exam periods. Further research to examine the framework nationally is required.