Federation soup next steps outlines some of the issues involved in interconnecting federations in the federation soup.

Liberty Alliance has published Deployment Guidelines for Policy Decision Makers
and a Legal Framework on federation agreements, with information about different federation types.

At the Terena conference TNC2007 we publised a paper on inter-federation agreements, Towards Interconnecting the Nordic Identity Federations with the Kalmar eIdentity Union as our case. The Kalmar eIdentity Union puts in place an inter-federation between the academic federations in the Nordic countries.

A kinder gentler federation agreement proposed by someone from the industry side.