A survey instrument developed to measure the perceived performance of the six components of an electronic performance support system (EPSS) and the perceived benefits of EPSS use was mailed to 182 target EPSS co-ordinators. A total of 98 (54.0%) questionnaires were returned. Of these, there were 79 (80.6%) usable surveys. Research results indicate that all six components of an EPSS were perceived to be effective by survey respondents during their use of EPSS. The user interface and online help/reference components were perceived as the most effective components, but they were not the components that made the greatest contribution to the perceived overall benefit of EPSS use. The highest relative contributors to the perceived overall benefit of EPSS use were the data/information base and an advisory system of job-oriented or problem-solving components. However, these two components were not perceived to be the most effective ones. This result also reveals that the perceived level of performance of the components of an EPSS was not absolutely reflected in the perceived level of overall benefit associated with EPSS use.