This paper examines some major theoretical and methodological problems in doing research on murder clearances. Clearances often rely on information supplied by third parties; research on third parties focuses on their role as mediators and facilitators, and as passive observers. This paper offers a view of third parties as knowledgeable people in the community whose cooperation with the police is problematic. The methodological section of the paper discusses the difficulties in using Supplementary Homicide Reports (SHR) to study clearances, and ways of coping with the problem of missing data. 1 table, 1 figure, and 26 references