A simulation modelling approach is used to assess the respective performances of different regimes of quota allocation (fixed or transferable), quota ownership (owned or not by fishers), and taxation for catching fish above quota. The simulations account for a variety of fleet behaviours (ranging from fixed by tradition to dynamic economics-driven). The modelling framework is applied to the Channel flatfish mixed fisheries. Transferable quota allocation regimes would particularly benefit small netters and beam trawlers, which would achieve a profit of (sic)50-150 million without compromising the conservation of eastern Channel sole, but it could impair the sustainability of other stocks. If quota is owned by fishers, the least fishing-efficient fleet stops fishing, but makes substantial profit from leasing quotas to beam trawlers and to small and large netters, which remain actively fishing. The highest economic return for quota owners ((sic)200-300 million) is achieved when effort allocation is fixed by tradition. The profit achieved by small netters is greatest when fleets are almost entirely economics-driven. Increasing overquota landing taxes generally leads to conservation benefits for all stocks, but at the expense of lower profitability for the fishery overall.