Discards represent a significant proportion of global marine catches and are generally thought to constitute waste or suboptimal use of fishery resources. A number of United Nations resolutions have drawn attention to the need to monitor and reduce discards and unwanted bycatch, in order to assess the impact of discards on marine resources and promote technologies and other means of reducing them. This paper provides an update of the quantity of discards in the worlds marine fisheries based on a fishery-by-fishery approach. The previous FAO estimate of discards at a global level, based on data prior to 1994, is now considered outdated. The present study re-estimates discards at a global level using information from a broad range of fisheries in all continents. Selected policy and technical issues are highlighted and suggestions made for future actions. A road map for achieving further precision in the global estimate is described and associated initiatives are outlined.