The California Commission for Teacher Preparation and Licensing sponsored the Beginning Teacher Evaluation Study (BTES) with funds provided by the National Institute of Education (Department of Health, Education and Welfare). The study was a multi-phase project which began in 1972 and was completed in June 1978. The overall purpose of the research program was to identify teaching behaviors which are effective in promoting learning in reading and mathematics in elementary schools. After Phase I, a general planning year (1972-1973), the Commission contracted with the Educational Testing Service (ETS) to conduct Phase II (1973-1974) of the program. During Phase II extensive field work was carried out in order to relate observed classroom behavior to student performance. The results of Phase II were used as one of the starting points for subsequent phases of the program. From 1974-1978 the BTES was conducted by the Far West Laboratory for Educational Research and Development. During those years there were three major data collection periods: Phase III-A (1974-1975), Phase III-A Continuation (1975-1976), and Phase III-B (1976-1977). A machine-readable user's manual and codebook defining the variables on file are available for these three major phases.