This report describes recent patterns of racial enrollments in private K-12 schools in the United States. It includes data from the federal government's most recent Private School Survey, which covers 1997-98. Results indicate that segregation levels are quite high among private schools, particularly among Catholic and other religious private schools. Black-white and Latino-white segregation is greater among private schools than public schools. White students are more racially isolated in private schools than public schools. Among private schools, secular private schools have the most racially diverse enrollments and lowest levels of segregation. White and Asian students enroll in private schools at two times the rate of black and Latino students. Private school enrollment rates are much higher among middle- and high-income families than low-income families. Differences in white and minority private school enrollment rates contribute substantially to overall patterns of segregation in many local school markets. Four appendices present data on state private school enrollment patterns, metropolitan area private school enrollment patterns, detailed school segregation tables, and regression models predicting white private school enrollment rates.