Successful organizations continually seek ways to improve productivity, reduce and control costs, and increase efficiency. Governmental entities also are driven by the need for increased efficiency and accountability in public service for their constituents.There is a continuing need for better tools and a number of government entities have turned to performance management systems due to their promise of improvement in various areas of productivity and accountability. This research focused on one such system, Six Sigma, which has recently experienced widespread adoption in industry in the United States, internationally, and in some government organizations. In this study Six Sigma was compared and contrasted with several performance management systems, and its effects and organizational cultural impacts on one organization were examined.The study investigated the financial implications and perceptions of organizational cultural change resulting from the Six Sigma system implementation in a large government enterprise. The first part of the study used the organization’s published financial information from 1997 through 2006 to determine whether there was a tangible financial benefit of implementing Six Sigma. The analysis indicated that the financial implications were statistically significant and quantified them as material and relevant to the organization’s two major business units.The second component of the research explored differences in organizational culture and attitudes among and between selected employee groups through the use of interviews and a survey instrument. Interviews were also conducted with a purposive sample of the executives who were involved in the decisions to implement Six Sigma. The Organizational Culture Inventory© and Organizational Effectiveness Inventory™ survey instruments were used to measure the organizational culture perceptions of the employee groups. Discriminant function analysis results suggested that the various groups shared a common organizational culture, which supports the null hypothesis that there were no differences in the organizational cultural perceptions among the organizational groups investigated.