Work system has been used loosely in many areas. This article concerns its use in understanding IT-reliant systems in organizations. A notable use of the term occurred in 1977 in the first volume of MIS Quarterly in two articles by Bostrom and Heinen (1977). Later Sumner and Ryan (1994) used it to explain problems in the adoption of CASE. A number of socio-technical systems researchers such as Trist and Mumford also used the term occasionally, but seemed not to define it in detail. In contrast, the work system approach defines work system carefully and uses it as a basic analytical concept.
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