The goal of all radiology information technology (IT) support organizations is excellent customer service through the availability of critical clinical information services, such as picture archiving communication systems and radiology information systems. Despite these goals, IT support personnel often act like firefighters, reacting to each problem, but unable to prevent or predict other problems. Proactive support is always more desirable than reactive support. Warning signs may exist well before a technical issue becomes system wide or the user is affected. The objective for IT support organizations in health care should be to maximize system uptime by using proactive monitoring systems for failures and to automatically detect failures through systems management tools. We report on the implementation of Nagios, an open source monitoring tool, as an availability management system in a diagnostic imaging department and on customized applications and protocols specific to radiology needs.