Ichnology - the stuy of fossil and recent traces of organisms - has yielded considerable information that is valuable in such fields as paleontology, sedimentology, and environmental reconstruction. Many of the basic concepts and definitions in ichnology are misused or misunderstood in current literature, however, which stresses the need for more stability or uniformity within the subdiscipline. With that goal in mind, a meaningful synthesis and evaluation of these basic concepts has been attempted in this paper; the views presented represent a consensus among 33 competent specialists from 12 countries, who criticized the original manuscript.