Empirical studies of open-access fisheries provide many examples where the market mechanism fails to achieve the optimal balance between levels of capital and labour in the fishery and the levels in the rest of the economy. Economic management of the industries generally requires drastic reduction in fishing activity in order to restore overall productivity. In practice, successful management of fishery resources needs to be based on models which integrate the economic and the biological processes. Maximum economic yield provides a clear-cut guide to the correct balance between output from the fishery and the rest of the economy. The economic objective is applicable to a wide range of biological models which may include stochastic and dynamic elements, whereas maximum sustainable yield is solely an equilibrium concept. In Australia and elsewhere it is well understood by fisheries managers and fishermen alike.