In recent years there has been a tremendous increase in the development of expert systems in organizations. This increased development is straining the already limited supply of qualified expert system developers. These expert system developers have come to be known as knowledge engineers, and their job as knowledge engineering. The process of knowledge engineering is divided into two tasks: knowledge acquisition and expert system construction. Knowledge acquisition has been defined as "The process of extracting, structuring, and organizing knowledge from several sources, usually human experts, so it can be used in a program" (Waterman 1986, p. 392). This process of knowledge acquisition has been identified as the "bottleneck" that currently constrains the development of expert systems. This paper summarizes what is known about the skills required and the techniques utilized in the knowledge acquisition process. Due to the similarities that exist between expert systems and traditional systems development, the literature pertaining to traditional information requirements determination and to systems analysts will be utilized to guide this exploration. Case study reports of actual expert system development projects and the practitioner literature will also be referenced. Given the lack of research in this area, future research directions are suggested to aid in developing a better understanding of the knowledge acquisition process. Pursuing these research questions should lead to the identification of· the skills and techniques necessary to successfully perform knowledge acquisition. Once these skills have been identified, selection and training programs can be developed to help reduce the shortage of qualified knowledge engineers and, ultimately, facilitate the increased development of expert systems in organizations.