Wizard of Oz experiments allow designers and developers to see the reactions of people as they interact with to-bedeveloped technologies. At the Centre for Interaction Design at Edinburgh Napier University we are developing a Wizard of Oz system to inform and further the design and development of Companion based technologies. Companions are intelligent, persistent, personalised, multimodal, natural language interfaces to the Internet and resources such as photo or music collections. They have the potential of turning our current human-machine interactions into human-machine relationships. In particular, a Companion prototype for reminiscing about a photo collection, called PhotoPal, is being used in our experiments. Several Wizard of Oz experiments have been run to assess people’s reactions and thoughts about using a Companion interface. The feedback from these experiments has informed both the design direction and choice of development technologies going forward. The Wizard of Oz system has also been put to use in a classroom of young pupils and to aid adults make more productive use of the Internet for learning. Further experiments to investigate the appropriateness of Companion dialogue are planned.