Determination of when a latent print was deposited on a surface has been largely a matter of speculation subject to considerable error. Estimates as to the longevity of a latent print must consider a variety of factors, including residue composition, physical and environmental stresses, and other conditions associated with the placement and durability of the print. The studies and cases reviewed in this article reveal a wide variation in the ability of a latent print to survive, even under harsh conditions. Consequently, the development of a latent print at a crime scene is no guarantee that the print has been recently placed. Also, the studies suggest that no reliable indication of a print's freshness can be obtained from its rate of development or appearance after it is developed. Because of their importance in criminal cases, reliable approaches to the estimation of the age of a latent print are needed; however, until they are tested and shown to be reliable, speculation or court testimony regarding the time when a latent print was placed can be effectively challenged and may undermine the professional reputation and credibility of an examiner. 15 references