Researchers interviewed 83 social scientists, 70 attorneys, and 10 federal district judges to discover their views on the use of expert social science testimony in school desegregation litigation. Selected from 17 desegregation cases adjudicated in federal district courts since 1970, the interviewees were asked about their roles in the litigation; their courtroom experiences and conflicts; preparation for the role; methods of handling opponents; and their perceptions of the impact of expert testimony, key desegregation issues, and the proper function of social science testimony. The findings indicate that most social scientists experienced conflict between the roles of scholar and witness and between their courtroom role and their personal political positions. Attorneys felt no such conflicts and consciously used expert testimony to educate judges about segregation as well as to undermine opponents' arguments. The authors also discuss interviewees' psycholoqical, strategic, and factual preparations for testifying; the characteristics of effective witnesses; cross-examination tactics; the strategies of collaboration, conversion, or coercion that attorneys used to influence judges; the use of witness panels; and the underutilization of social science expertise in implementing desegregation decisions. The study's interview schedules are appended. (Author/RW)