Notification Collage
posting ephemeral information onto a distributed group surface

The Notification Collage (NC) is a groupware system where distributed and co-located colleagues comprising a small community post media elements onto a real-time collaborative surface that all members can see. The NC randomly places incoming assorted media on its surface: live video from desktop cameras; editable sticky notes; slide shows displaying a series of digital photos, among others.

The NC can become a rich forum for discussions in the community it represents. Video on the NC lets everyone 'see each other' via the internet, while the availability of postit notes frequently results in both formal and informal discussions about various topics. Not requiring direct attention, the NC generally resides on a large public display, or even a secondary personal display that can be turned transparent: this allows work to be performed beneath it while still being able to observe changes to the collage.

Primary Investigators

Michael Rounding (MSc research)
Saul Greenberg (Supervisor)


  • System used for several years in our research laboratory
  • System used as the basis for a tech-transfer grant project

Current Status

  • Project completed
  • See Community Bar project for the next generation work around this concept

Key Publications

Rounding, M. (2004)
Informal Awareness and Casual Interaction with the Notification Collage. Master's thesis, Department of Computer Science, University of Calgary, Calgary, Alberta, Canada, April.
PDF Paper
Greenberg, S. and Rounding, M. (2001)
The Notification Collage: Posting Information to Public and Personal Displays. In Proceedings of the ACM Conference on Human Factors in Computing Systems - ACM CHI'01. ACM Press, pages 515-521. See also video shown at the conference. Earler version as Report 2000-667-19, September.
PDF Paper PowerPoint Presentation
Rounding, M. and Greenberg, S. (2001)
Notification Collage. Research report iLab-2001-01, Grouplab, Dept. Computer Science, University of Calgary. Presented publicly in Greenberg and Rounding's ACM CHI 2001 presentation.
Video File

Other Publications

Rounding, M. and Greenberg, S. (2000)
Using the Notification Collage for Casual Interaction. In Workshop on Shared Environments to Support Face-to-Face Collaboration, held at ACM Conference on Computer Supported Cooperative Work - ACM CSCW'00. (Philadelphia, Pennsylvania, USA),, December. Online proceedings available at See also presentation.
PDF Paper PowerPoint Presentation