Abstract-- Service discovery enables users to access information, resources and services anytime, anywhere. This involves a client, a service provider and an infrastructure for service registration and lookup. Clients use service discovery protocols (SDPs) to issue a service request to a service registry or an individual service provider. In this paper we investigate the suitability of existing SDPs for mobile users in an ambient intelligence context. After reviewing the most well-known SDPs, common problems in the domain of user mobility and solutions that are currently available are discussed. Keywords--Service discovery, ambient intelligence, mobile computing, ad-hoc networking. Presentation--Should this paper be accepted, it will be presented by Davy Preuveneers.