With the decline of enrollment at a number of community colleges there is a demand for accurate enrollment projections, yet enrollment is increasingly difficult to forecast. Student body composition has changed markedly from the traditional 18 year old group as the percentage of women and part-time students and students' ages have increased. Also, many students enroll for only one semester. In order to accurately monitor and maintain enrollment, colleges must use existing college and community data to assess population trends. More emphasis must be placed on community educational needs and the development of promotional, delivery, and evaluation techniques. Because changes in student body composition may result from changes in programs and services, institutional research staffs should work closely with persons responsible for student recruitment and changes in curriculum, delivery systems, and college services. The generated data can be used to monitor the effectiveness of change, to identify where changes could be made in curriculum or services, and pinpoint potential problems that may result from not making changes. (Research office staffing and components of the necessary enrollment and population data base are discussed in appendices, and are illustrated with samples of data analyses.) (TR)