This work deals with the synchronisation §of social network services. This type of internet §application enjoys great popularity which results§in new challenges for identity and relation §management. On one side the user has to manage §different identities and on the other side a §friendslist per social network service. From this §efforts arose to make data portable and§reusable for example in order to avoid re-declaring §friends on every site. To accomplish this goal §numerous projects and technologies have been §developed, which already provide partial solutions §for this problem. The basic conceptual question §however how to deal with the problem generally is §still open. Moreover some of the techniques are only §suitable for special use cases or else not ready for §a professional use. In this thesis some of the §existing standards shall be used to tie them together §to one total system. This system consists out of a §central identity provider, which functions as a §central storage for the users contact data. By §utilising interfaces this contact data§can be exchanged with the social network service and §by that improves the relation management for the §users.