In March 1995, a Home Office letter to chief constables announced that all police forces would be required to introduce a system of ethnic monitoring of suspects and offenders from April 1996. The introduction of this policy reflected mounting concern about the lack of hard evidence in the debate on "race and crime." This study found major difference among and within forces in their policies and practices of ethnic monitoring, including their recorded use of various powers available to them and the quality, coverage, and comparability of the statistics they collect generally. Further, it is uncertain whether and to what extent ethnic monitoring will mesh with other police concerns that have higher priority. Also, the ethnic composition of the populations served by forces varies considerably; only 8 out of the 43 forces in England and Wales have ethnic minority populations at or above the national average. Findings show that most police officers viewed ethnic monitoring as irrelevant at best; at worst, it was resented and/or feared as a condemnation of their practices in relation to ethnic minorities. Of those who supported the practice, some did so because they believed the documentation would support their claims to treat all groups fairly; others supported the practice because they believed it would show ethnic differences in levels and patterns of involvement in crime rather than discriminatory police practices. The study concludes that nationally, the data produced by ethnic monitoring will come into their own within the next few years, once they are able reliably to show trends and when they can be compared with data from the Crown Prosecutors Service and the courts to provide a picture of the criminal justice process overall. The current research suggests that the figures for black people may be inflated because of heightened police suspicion of black people and by more adversarial contact with them. These contacts both reflect and reinforce negative perceptions between police and black citizens that have developed over decades. The police exercise of their powers in these encounters may rarely constitute overt discrimination, but the debate on race and crime may not have given sufficient attention to the exercise of police discretion. 57 references and extensive tables and figures