Mobile XSiena is a novel publish/subscribe platform which seeks to extend the XSiena content-based publish/subscribe system in order to support user mobility and create an experimental framework to study the relationship between such mobility and pervasive information dissemination flows. Categories and Subject Descriptors H.3.4 [Systems and Software]: Distributed Systems General Terms Design, Performance, Experimentation Keywords Event-Based Systems, Publish/Subscribe, Mobility Support