In this aricle we propose EC-XAMAS, an XML-based adaptive multi-agent system for handling e-commerce activities. More specifically, EC-XAMAS aims at supporting a customer visiting an e-commerce site in the search of products and/or services present therein and appearing to be appealing according to her past interests and behavior. The system is adaptive with respect to the profile of both the customer and the device she is exploiting for visiting the site. Finally, it is XML based since XML is exploited for both storing the agent ontologies and handling the agent communication.