The use of electronic media for economic transactions adds a new potential to the vendor-buyer relationship. It gives the customer a voice, an input channel from which he or she can participate in a number of activities such as product development, feedback, support for other customers, recommendations etc. This can be in the form of active participation or simply a sharing of preferences. The structuring and organization of this participation may empower the customer and may result in new kinds of dynamics in customer collaboration. Personalization is increasingly considered to be an important ingredient of Web applications. In most cases personalization techniques are used for tailoring information services to personal user needs. In marketing, personalization supports one-to-one marketing (Peppers & Rogers 1997) which should increase the customer share over a lifetime. Platforms for communities of transaction can result in an enriched product catalog, which Schubert (2000) termed âParticipatory Product Catalogâ. What used to be possible in the corner shop, since the shopkeeper knew her customers personally, will be extensively possible in the electronic medium by the storage of profiles and the automatic evaluation on the basis of predefined rules. With the use of electronic media, the advantages of mass marketing (the same online- shop and standardized customer communication) are harnessed to the strengths of personalized customer communication and may lead to collaborative customization as a powerful support mechanism in customer relationship management (Schubert & Koch 2002). In this short paper we will briefly sketch some initial ideas from a research project that aims at enabling the collaborative customization of individual products based on personalization and community communication.