This paper presents experiences from Robotics, a long-term project at the Swiss National Exposition Expo.02, where mobile robots served as tour guides. It includes a description of the design and implementation of the robot and addresses reliability and safety aspects, which are important when operating robots in public spaces. It also presents an assessment of human–robot interaction during the exhibition. In order to understand the objectives of interaction, the exhibition itself is described. This includes details of how the human–robot interaction capabilities of the robots have evolved over a 5-month period. Requirements for the robotic system are explained, and it is shown how the design goals of reliability and safe operability, and effective interaction, were achieved through appropriate choice of hardware and software, and the inclusion of redundant features. The modalities of the robot system with interactive functions are presented in detail. Perceptive elements (motion detection, face tracking, speech recognition, buttons) are distinguished from expressive ones (robotic face, speech synthesis, colored button lights). An approach for combining stage-play and reactive scenarios is presented. The authors also explain how an emotional state machine was used to create convincing robot expressions. Experimental results, both technical and those based on a visitor survey, as well as a qualitative discussion, give a detailed report on the authors’ experiences in this project.