'Formal informality' in EU external migration governance: the case of mobility partnerships

External migration has become a site for extensive EU activity, not least in the years following the start of the migration 'crisis' in 2015-2016. It has also become a testing ground for forms of governance that are not generally associated with external relations. We term this type of governance 'formal informality' as there is the appearance of an EU agreement with a third country but lacking the legal protections or transparency for actions taken under it. The informality associated with tools of governance is potentially problematic when used to bypass the substantive and procedural formalities associated with law, and which in turn ensure transparency and the protection of rights. This article uses the emergence and evolution of Mobility Partnerships between the EU and third countries as a prism to analyse what the moves towards informality mean for the governance of external migration.