A method of determining a requirements characterization profile for an entity is disclosed. The method comprises the steps of receiving classification parameters defining a requirement for an entity and selecting, in dependence on the classification parameters, a set of entities from a database of previously assessed entities. The method further comprises retrieving from the database characterization parameters of the selected set of entities, and constructing, in dependence on the characterization parameters, a requirements characterization profile for the entity. An apparatus is provided that comprised means for performing such a method.