What controls the “genitive variation” in Present-Day English?

This paper takes up the recent discussion of what controls speakers’ use of the -s and of- genitives, as in the university’s budget and the budget of the university. Most of the paper deals directly with control of that “genitive variation”. It first argues that there is a third variant, as in the university budget. It then discusses why all three just given, for example, are grammatical, but, with a litre of petrol, the alternatives (*a petrol’s litre and *a petrol litre) are not grammatical, arguing that the grammaticality is controlled by whether the word and phrase meanings are compatible with their syntax. It then argues that, where there are equally grammatical alternatives, the speakers’ choice often depends on the same issues of semantic and syntactic compatibility. The last main section of the paper deals with the grammatical status of that third variant, arguing that the university budget truly is genitive.