Trust and its role in e-commerce is a major topic for researchers, clients, and service providers alike. However, questions of origin and practical usage of trust in e-commerce are still not answered. Two eminent obstacles in the integration of information on trust and reputation are limited data about customers, and a missing fine grained access control model. The first hindrance is shrinking as users generate personal data in the Web 2.0 as they go (or rather surf). The aim of this paper is to show potentials for e-commerce federations using an attribute-based authentication and authorisation infrastructure to use customer information for the derivation of metric trust and reputation values. Using Fuzzy Cognitive Maps and trust metrics, a prototype integrates a federation’s user data within an easy to use service provider interface for reputation management. To assure user privacy the data is categorised and stored distributedly.