The creation of new populations of rare and endangered plant species has become well-established as a standard technique in conservation and restoration ecology. However, much remains unknown about the actual rates of success or failure of such reintroductions. Recent research suggests that in part this reflects under-reporting of failures. In 2000, the authors published a paper reporting rates of success in reintroducing eight perennial plant species into two reserves near Boston, MA, in 1994–1995. In 2010, the authors conducted a recensus of the experimental sites 15 years after reintroduction; almost all the populations reported in 2000 had disappeared. The implications for reintroduction methodology, with respect to establishing and reporting both successful and unsuccessful experiments are discussed.