This is one of a series of reports which provide definitions of and descriptive data on the variables used in the Comparative Study of Phase IV of the Individually Guided Education (IEG) Evaluation Project. Phase IV investigated three curriculum programs specifically designed to be compatible with instructional programming for the individual student: (1) the Wisconsin Design for Reading Skills Development (WDRSD); (2) Developing Mathematical Processes (DMP); and (3) Prereading Skills (PRS). Information on instructional methods and pupil outcomes for grades 2 and 5 was collected from achievement monitoring and domain referenced tests, teacher logs, and classroom observations. Information on background, organizational, and program variables came from questionnaires completed during structured interviews with principals, unit leaders, and teachers. This paper focuses on six background variables: Demographic Background, Teacher Experience, Interorganizational Relations, Procedures Fostering Coordination and Development of the School Program, Intraorganizational Structure, and General Implementation of the Instructional Programming Model. For each variable, the report includes a verbal definition, a list of the questionnaire items from which the variable was developed, a detailed explanation of the scaling procedures, and a description of the distribution of the variable in the 19 participating schools. (Author/BS).