The vital, sometimes controversial contribution of private schools to American education is documented by data gathered from 1976 to 1979. Although the totals reported are estimates because many values had to be statistically imputed, many patterns emerge. The proportion of private schools to all schools has varied only slightly since 1932. Although the number of private schools is currently decreasing at a faster rate than the number of public schools, private enrollment shows a slower decline. Eighteen percent of all elementary and secondary schools are private. Private schools enroll over 10% of all students; employ 11% of all teachers; account for 10% of all high school graduates; and generate and spend about 6% of the total amount spent for elementary and secondary education. Among private schools, 80% have church affiliation; 50% are Catholic schools enrolling 64% of all private school pupils. Enrollments in Catholic schools are declining but those in other church schools are rising. Also, 65% of private schools are elementary level with 59% of all private schools students; 12% are secondary with 21% of the students; and 17% combine both levels with 18% of the students. Pupil-teacher ratios are generally lower than the 1976 public school average. (SB)