Andrew H. J. Harrop, J. Martin Collinson and Tim Melling Abstract There is a tendency to see examples of fraud in ornithology as rare aberrations. This paper outlines some known and suspected historical examples of fraud, and argues that fraud of one kind or another has occurred more or less consistently, if uncommonly, in ornithology. Although most of the examples discussed are from Britain, it is likely that similar examples could be found in the archives of many nations. It is also likely that small-scale fraud continues today and is something that the ornithological community should be aware of. In particular, this has implications for the level of proof required by those assessing records of rarities.