This paper describes the structure and function of the SYS IV PLATO Curriculum Project's (PCP) computer-based management system and justifies the system design. A consideration of features most critical in the design of management systems provides the context for a discussion of specific SYS IV features, which include its ability to deliver any type of lesson in a variety of different management configurations; capacity for contingent branching; division into a fixed and variable part, which makes possible its flexibility and ease of use; and its unique methods for presenting, summarizing, and storing data in varied formats. Design considerations are addressed as a set of tradeoffs: power versus wide applicability, flexibility versus ease of use, and amount versus accessibility of data. The technical means by which features are provided are explained, including the programing language, Instructor Logic (IL), and the SYS IV options of index, topic size, instructional type, assignment, saving data, learning path, instructional intervention, delays, records options, and the implementation scan utility, which groups data for reports, tabulations, and summaries. A conclusion summarizes system advantages and the need for "computer imagination" to actualize the potential for computers in education. (LMM)