The rules of conduct that must be followed on all official business between different supernatural organizations.

Unseelie Accords were signed in the relatively recent past (within the last decade) and the signatories include pretty much every major power – Both Faerie Courts, the Vampire Courts, The White Council, and even The Order of the Blackened Denarius.

It’s pretty much the system that everyone has agreed to work under, for the time being. It includes things like designated neutral ground, a certain amount of courtesies, channels to go through for diplomatic measures, etc.

It’s also possible to be a Freeholding Lord under the Accords. This is a mechanism by which someone endorsed by people already party to the Accord can gain status under them.

And they’re totally engineered by Mab, the motives of which are… opaque, at best.