Net migration flows (about the regulation of which members of the RPI have been writing since 2017) are again a hot topic in political debate. In this latest blog, the Insights team briefly sketches out a potential, alternative way of looking at the issues: a different ‘gestalt’, based on a tradeable right to residency, which does not need to rely heavily on enforcement by coerced deportations (difficult in practice) or creating ‘hostile social environments’. Rather, it simultaneously seeks to make unlawful immigration more financially expensive and emigration of residents more financially rewarding, in each case relative to the status quo. Even in a bare bones form, it could give government three immediate ‘control variables’: the total number of rights available, the level of financial penalty for unlawful immigration, and the level of the bid-ask spread in the purchase or sale of the relevant right.