Models are urgently required that will allow stock assessment for fisheries in which a significant component of the catch is taken by recreational fishers, where these models will rely on abundance indices from the commercial fishery, occasional length or age composition samples from the total catch and occasional estimates of total catch. Given the expense associated with recreational surveys, there is a need for the development of an approach that would allow determination of an appropriate frequency for such creel censuses in order that they might provide the data necessary to achieve a specified level of precision from the resulting stock assessment. A method is required that will allow an assessment of the value of data derived from commercial fisheries statistics for use in assessing the stocks that are shared by recreational and commercial fishers, prior to making final management decisions on catch re-allocation from the commercial to the recreational fishing sector.