One of the challenges in conducting criminological research is addressing and understanding the law regarding protection and disclosure of sources and/or information regarding offenses or intentions to commit offenses. This paper describes how the challenge has been addressed by researchers in criminology, sets out the position in the United Kingdom, and examines a range of issues involved. At one end of the approaches by researchers to disclosure are those who would disclose in some circumstances, as part of an obligation as a citizen to report illegal activities to the authorities. To adopt a neutral stance towards these law-breaking activities reinforces the offenders' criminal behavior. Legislation in the United Kingdom establishes penalties for failing to disclose to the police information about offenses, and allows a range of law enforcement and judicial bodies to require disclosure. Two countervailing legal issues in any consideration of disclosure are confidentiality and libel. The article concludes that the researcher who chooses in advance to research offending behavior with a clear commitment to not disclose details of offenses takes a bold step. Nevertheless, the research community has a vested interest in ensuring that mistakes are not made that unnecessarily damage the reputations of researchers, harm respondents, or undermine future research. Notes, references