Fifty-four inner city Catholic and other private elementary schools, whose student population is at least 70 percent minority, were studied to determine their educational impact, to describe pupils' family backgrounds, and to identify factors that influence academic achievement and school effectiveness. The study found that: (1) clientele of these schools have lower income levels than the national population; (2) parents have modestly high educational levels; (3) parents value quality education and religious education as separate motives for sending children to private schools; (4) strong bonds link teachers, administrators, parishes, and parents; (5) teachers are motivated by intrinsic job satisfaction more than by money; (6) the schools show modest propensity toward selectivity through admission but not through expulsions; (7) the schools face socialization problems, but have demonstrated some success in dealing with discipline problems; (8) school factors, especially teacher attitudes and students' school experience, influence student behavior and achievement; (9) school effectiveness is enhanced by socialization-oriented school policy and school-community cooperation; (10) parents rate school quality highly; and (11) the schools do not enhance white flight. It was also found, however, that the survival of inner city private schools is threatened by financial problems, decreasing numbers of religious faculty, and deteriorating facilities. (Author/MJL)