Abstract We show that the set of all separable Banach spaces that have the π-property is a Borel subset of the set of all closed subspaces of C (Δ), where Δ is the Cantor set, equipped with the standard Effros-Borel structure. We show that if α< ω 1, the set of spaces with Szlenk index at most α which have a shrinking FDD is Borel