—Collaborations by the use of inter-organizational business processes can help companies to achieve a competitive edge over competing businesses. Typically, these collaborations require an efficient identity management (IdM) that ensures the authorized access to services in different security domains. The successful implementation of an IdM in distributed systems requires to cope with a diversity of systems and to manage the challenges of integration. While integration should not introduce an unnecessary degree of dependence and complexity, various IdM goals should be achieved by integration: in particular, collaboration-wide consistency of identity information. Due to its decentralized and modular design, a federated identity management (FIM) approach is a promising strategy in distributed systems. Our thesis is that the distributed character and heterogeneity of involved systems requires appropriate informationconsistency mechanisms that go beyond what is offered by current FIM pr...