This proposed study is to investigate the design and development process of electronic performance support systems (EPSSs). The primary purpose of this study is to help the EPSS designers by proposing a more effective and productive EPSS design and developmental model. By analyzing EPSS products and observing EPSS design projects, the research will propose a design model for future EPSS designers. Discussion includes what makes EPSS different; the need for an EPSS design/development approach; current approaches to EPSS design/development and their problems; help from other fields; information systems design and EPSS; and Chaos theory (dynamic systems or adaptive development). The paper concludes that EPSS development is at the edge of technology, and it requires a mixture of Chaos-based top-down and bottom-up processes. (Contains 55 references.) (Author/AEF)