It is widely accepted today that the global order contains a multiplicity of different normative orders. While the legal status of some of these normativities – especially those of an informal character and private origin – is still debated, the importance of multiplicity for understanding and theorizing law beyond the state is hardly disputed. Yet unlike some in the pluralist literature assume, this multiplicity is not one of parallel existence, but of intense entanglement and interaction. This paper is interested in the shape of this interaction: it seeks to shed light on how the different legalities in the global order interact and what interface norms are emerging at the points where legalities intersect. It will present a typology of interface norms, both formal and substantive, and a set of examples in which we observe these norms, with a view to providing a prism that can help us structure deeper inquiries into the interface law that is emerging in the global realm.