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The 2011 assessment for the Chesapeake Bay blue crab fishery uses a sex-specific catch multiple survey analysis (SSCMSA) model. This is a major improvement on the 2005 assessment primarily because of the integration of the reference point calculations within the model using per recruit analyses. Previously, the population model and the calculation of reference points were two separate processes which were not necessarily consistent. The two main differences from the 2005 model are the inclusion of a renewal function in the form of a stock–recruitment relationship, and the incorporation of separate components for each sex, which allows the generation of sex-specific reference points. This is particularly important considering recent management changes which have been geared to conservation of the female stock and which have consequently changed the sex-specific exploitation rates. The assessment is a two stage (age-0 and age-1+ crabs) model, which incorporates three fishery-independent surveys including the extensive winter dredge survey, which is treated as an absolute index of abundance. Two main concerns with the formulation and robustness of the model were identified. Firstly, the stock-recruitment relationship is based on both males and females, and whilst it is an innovative approach, the way in which the relationship i