This paper reports the findings of a national study of the impact of school desegregation programs on white public school enrollment from 1968 to 1976. School districts studied were grouped according to region, metropolitan status, and source of pressure to desegregate. It was found that only central city districts that had been subjected to court pressure to desegregate experienced substantial declines in white enrollment. These declines reflect long-term trends, and appear to be associated more with the implementation of a desegregation program than with the actual change in racial isolation (the proportion of black pupils in the school of the average white child) brought about by such desegregation programs. (Author/WAM)