Examined in this paper are the characteristics that distinguish successful schools from unsuccessful schools. Particular attention is given to the instructional success of schools with poor children. An extensive review of related literature illustrates the wide range of opinions held by educators and researchers on the subject. Reference is made to studies and literature dealing with compensatory education programs, school characteristics, and family and social background. Some of the factors discussed and evaluated include school size, teacher experience, teacher's race, teacher salaries, per pupil expenditure, and school facilities. Reference is also made to school studies that are most explicit in identifying and advocating particular changes. Described are certain aspects of school organization, instructional strategies, and school-community dynamics that seem most relevant to achievement gains for poor children. Factors that seem to be the most tangible and indispensible characteristics of effective schools are summarized. Included are such factors as strong administrative leadership, school expectations, school atmosphere, emphasis on basic skills, and frequent monitoring of student progress. (Author/EB)