-We extend the study of human-robot interaction into the area of large-scale, multi-user, robotic interactive environments.Using our experimental infrastructure -the interactive space Ada, an exhibit at the Swiss national expo in 2002 that received 553,700 visitors -we show that human movement is predictive of key attitudes towards a space and other humans, and that subjects' behavior and attitudes are influenced by subtle modifications of environmental parameters.We also found several demographic effects on visitors' opinions of interactive spaces. These findings enhance our quantitative understanding of collective human behavior in interactive spaces and are a first step towards the construction of active environments that can automatically influence human motion and experience. This knowledge will be important in the design and construction of future interactive environments for enhancing the safety and enjoyment of shared areas for large numbers of people.Index Terms -human-machine interaction, interactive space, crowd behavior, human movement, human attitudes