The Data-Based Staff Development Program is an integral feature of the Adaptive Learning Environments Model (ALEM), an educational program developed to provide basic skills learning experiences that are adaptive to the individual learning needs of students. The Data-Based Staff Development Program was designed to assist school personnel responsible for implementing the ALEM in systematically incorporating relevant data on the degree of program implementation and students' learning progress in analyses of their staff development needs. The goal is to provide a self-monitoring tool that helps school personnel become increasingly more independent in establishing and maintaining a high degree of ALEM implementation. During the 1980-81 school year, a pilot investigation of the effectiveness of this program in improving classroom implementation of the ALEM was conducted in ten elementary schools. Data were obtained through the use of three measures: (1) instruments measuring degree of program implementation; (2) school district staff development plans; and (3) monthly training logs kept by the schools' education specialists. The data were analyzed to investigate the relationship between staff development plans and program implementation needs as suggested in the degree of implementation scores for individual teachers. Preliminary evidence from the study supports the effectiveness of the program; more detailed studies in the future will be needed to confirm this finding. Tables illustrate the critical factors used in analyses and the results of the study. (JD)