Tom W. Bell was on the Society and the State Podcast where he talked about Polycentric Law and Competitive Governance. The podcast episode is highly recommendable and can be listened to here:
For more information on Competitive Governance you can also check out the website of the Institute for Competitive Governance, which has recently been founded and whose Academic Director is Tom W. Bell. In particular, the reading list provided on the website is interesting.
To dive even deeper into the topic you can read Bell’s book Your Next Government? – From the Nation State to Stateless Nations.