A Standish Group (1994) study showed that only 16% of all information technology projects come in on time and within budget. The situation is not better concerning health information systems. Many health information system implementations are less than completely successful (Berg, 2001; Giuse & Kuhn, 2003; Lorenzi & Riley, 2003). In this article, the health information system means “a system, whether automated or manual, that comprises people, machines and /or methods organized to collect, process, transmit, and disseminate” data that represent user information in healthcare (Kuhn & Giuse, 2001, pp. 275). What is successful implementation and whose success is measured? Successes can be measured in many ways. Delone and McLean have been finding out the success factors of management information system which are also applicable to health information system. The success factors are: system qualities, e.g., the ease of use or time savings, information quality, e.g., completeness or data accuracy, usage, e.g., the frequency of use or the number of entries, user satisfaction, e.g., user-friendliness or overall satisfaction, individual impact, e.g., changed work practices or direct benefits and organizational impact, e.g., communication and collaboration or impact on patient care. Furthermore, user involvement during system development, implementation and organizational culture have been identified as possible factors measuring the success. However, the need for further research to determine which attributes are the most useful ones in measuring success has also been revealed. (van der Meijden, Tange, Troost & Hashman, 2003).