Excellent book that lays out the options for specific models versus generalised models and the associated pros and cons. The answer is do both for different reasons and then understand how many of the business rules you want to enshrine in the data model. Builds on the first two books and shows how the authors wrote them. At the end of the day each modeller/designer must make their own calls but this provides some structure around which to make those choices. The detail wags the dog.