The different functions of an information system in critical care are: bedside charting, clinical record keeping, electronic prescribing (physician order entry), integration with other hospital systems, decision support, remote access, and multi-site communication. The information system generates an enormous amount of data. Attempting to keep all of it inevitably creates storage issues even in the age of the multilayer DVD and the terabyte hard drive. A good archiving system performs a form of triage on the data that is generated based on the duration of usefulness for that data. In order for the huge amount of data generated by the information system to continue to be useful it has to be converted to a database format. A successful implementation of the critical care information system requires an examination of every aspect of the workflow of the critical care unit and how the system will impact (and improve) on it.