Citywide has involved an extensive collaboration with the artists group Blast Theory with additional collaboration with BTexact and further support from Microsoft Research, BBC Online, The Arts Council of England, AHRB, The Institute of Contemporary Arts, b.tv, and V2.

Citywide began with series of exploratory workshops to develop new concepts and technologies that might be used in a citywide performance. We explored the use of handheld computers with GPS positioning and wireless communications to access a virtual world when moving through the physical world. We developed two generations of a stand-mounted mobile 3D display called the augurscope. We also prototyped various 'light-based' techniques, including projecting the shadows of avatars onto the city streets and using visually tracked flashlights as interaction devices.

We then staged and evaluated a first public performance called Can You See Me Now?. This took the form of a game in which online players were chased across a virtual city by three performers who were running through the actual city streets. Can You See Me Now? was staged in the cities of Sheffield, Rotterdam and Oldenberg between 2001 and 2003.

We then staged and evaluated a second public performance called Uncle Roy All Around You in London in 2003. This was an artistic performance in the form of a game in which street players journeyed through the streets of the city in search of the elusive Uncle Roy, guided by online players who were able to track their progress in a parallel 3D model of the city and send them messages in order to help or hinder them.

The Citywide performance project has followed the approach of staging public performances as a research method. This involves working with professional artists and commissioning bodies to create high-quality artistic products that are deployed in public on as large a scale as is possible. These experiences are then studied using a combination of ethnography; audience feedback; and analysis of system logs.

Citywide has helped us understand how participants actually experience uncertainties, such as those arising from inaccuracies in positioning, leading to new design strategies. We have also considered how artists can deliberately exploit the ambiguities arising from uncertainties. Beyond this, we have gained new insights into how artists design and orchestrate these kinds of real-time experiences.

Citywide has contributed several new devices to Equator's catalogue including the augurscope and visually tracked flashlights. Both of these were instrumental in shaping Equator's 'sense and sensibility' framework that supports the design of new devices through a systematic exploration of the boundary conditions between expected movements, those that can actually be sensed by a computer, and those that are desired by a computer.

Citywide's contributions to Equator's infrastructure have focused on the development of a game-engine to support multi-player mixed reality games that features new tools for artists to design and orchestrate experiences; support for distributing game events over intermittent wireless connections; and the mechanism of self-reported positioning in which location is established through use of an electronic map as an low-cost and reliable alternative to GPS.