This paper briefly reviews the current racial balance in Philadelphia, Pennsylvania public schools and discusses the development of an evaluation system to assess progress toward desegregation. Priority products and services of the Desegregation Evaluation Unit, formed in 1979, are listed. A number of problems that must be addressed in order for the school district to participate successfully in a voluntary desegreqation plan are discussed. Individual objectives, relating to racial balance, community involvement, staff development, and academic achievement, are outlined and ways of evaluating each objective are reviewed. Finally, serious barriers to voluntary desegregation are discussed, particularly the tendency toward "one way" desegregation; that is, minority students attend predominantly white schools, but few white students voluntarily attend schools in minority neighborhoods. (GC)