The doctrine of the properties of terms, which deals with the referential functions of expressions of speech in a sentential context, was one of the most important achievements of medieval philosophy. The second treatise of Albert of Saxony's 'Perutilis logica' treats as properties of terms: supposition and its sub-forms and the complementary properties of ampliation and appellation, as well as offering a commentated collection of rules for their use which is of unusual detail and quality. The 'Perutilis logica' is both by its content and its didactic value the most paradigmatic logical compendium of the 14th century, however the fact that it has as yet been little researched is probably due to the verdict of a widespread traditional orientation, particularly to Buridan. The study presented here tries to show on the basis of an interpretative analysis of the second treatise that the doctrine of the properties of terms is stated in an unusually developed form in the 'Perutilis logica' and suggestions that it lacks originality must be revised. The study is supplemented by an appendix containing an edition based on what is probably the earliest MS of 1356.