This paper reports on a case study of the organizational memory information system (OMIS) of an engineering group at a nuclear power plant. It found that the OMIS was effective based on the criteria of the competing values model (Quinn and Rohrbaugh, 1983). The engineering group was also considered to be effective based on the criteria used to evaluate effectiveness by the group managers. One of the criteria used to assess group effectiveness was the ability to use organizational memory and it was found that an improved OMIS resulted in improved organizational and individual effectiveness. The study also found that measurements of OMIS effectiveness could of been improved by refining the competing values model measurement of "integration" and by creating a measure for evaluating the reliance on individual's memories