Who do we trust to provide identity and access management services for our research collaborations? When do we decide to implement it ourselves versus relying on others? How do we create incentives for establishing trust? How do we bridge the gaps in trust, functionality, and reliability? In this presentation, Jim will review lessons learned from his experiences working with IGTF certificates, eduGAIN SAML assertions, and OpenID Connect claims for access to scientific research applications. What new challenges appear when moving from 1 to 10 to 100 to 1000 identity providers? Why does identity information flow more easily in some federations and not others? How do we determine what levels of assurance we need and find providers who can meet those needs? How do we mitigate the risks? How do we effectively federate services operated by the research community, higher education institutions, NRENs, and commercial providers?