The maximum amount of fish over a period of time (year, season) that can be produced by a fishing fleet if fully utilised while satisfying fishery management objectives designed to ensure sustainable fisheries: YT = Y (ET, S) in which YT is target yield or catch; ET is target effort generated by a fully-utilized fleet; and S is stock size (biomass). The "fishing fleet" is meant to be the stock of inputs (i.e. physical capital and human capital). The term "fully-utilized" is used in a precautionary context in that it is assumed that capacity utilisation is 100%. The maximum catch that capital stocks could remove can be determined by observing the fishery under study during a period with few restrictions.