Managers of healthcare organizations are increasingly aware that the potential of medical information systems exceeds mere support of routine administrative and clinical transaction processing. This chapter describes a case study about Maccabi Health Services, the second largest health maintenance organization in Israel and the first one to computerize clinical records resulting from routine transactions in doctors’ offices, laboratories, and pharmacies. In this case about decision-making support practices, recycling the content of existing databases made it possible to discover patterns of sub-optimal treatment without having to invest time and money in additional data-collection procedures. The case study thus demonstrates value-added utilization of patient data, beyond uses intended at the beginning, for effectively supporting the implementation and evaluation of disease-management programs. Lessons learned about organizational benefits reaped from the organization’s decision-support practices include implications for such initiatives as data warehousing, data mining, and online analytical processing.