© Springer-Verlag Berlin Heidelberg 2006 Implementing Privacy Negotiations in E-Commerce

Abstract. This paper examines how service providers may resolve the trade-off between their personalization efforts and users ’ individual privacy concerns. We analyze how negotiation techniques can lead to efficient contracts and how they can be integrated into existing technologies to overcome the shortcomings of static privacy policies. The analysis includes the identification of relevant and negotiable privacy dimensions for different usage domains. Negotiations in multi-channel retailing are examined as a detailed example. Based on a formal-ization of the user’s privacy revelation problem, we model the negotiation proc-ess as a Bayesian game where the service provider faces different types of us-ers. Finally an extension to P3P is proposed that allows a simple expression and implementation of negotiation processes. Support for this extension has been in-tegrated in the Mozilla browser.