Scientific progress depends on the free dissemination of original thinking and research. With the evidence base formed by publication, investigators develop and implement additional studies, and policy makers propose new laws and regulations. The ramifications of this evidence can affect millions of lives and reallocate considerable resources for programmes or research. As such, it is incumbent on investigators to conduct rigorous research, which precludes engaging in scientific misconduct such as falsification, fabrication and plagiarism. This article addresses the causes and consequences of plagiarism and the processes by which plagiarism is discovered. It concludes by considering the responsibilities of members of the research community in preventing and addressing plagiarism.