This paper discusses the HCI and usability evaluation techniques that were
deployed in three PPGIS studies— two that focused on PPGIS research and a study that
focused on usability— and will demonstrate the contribution of these techniques to
PPGIS research. The paper begins with a brief overview of the links between HCI and
usability evaluation and GIS. A brief history of HCI research and trends is discussed, as
well as related work that has been carried out within Geographic Information Science
(GISc). The second part of the paper builds on this theoretical background and
demonstrates how HCI and usability evaluation can contribute to PPGIS research and
practice. Based on our experience, the contribution of these fields to PPGIS research is
outlined first. The contribution of PPGIS to usability is then explained. The final section
of the paper discusses these findings within the broader PPGIS framework and suggests
that an iterative development process is needed in projects and research wishing to
improve the use of the technology and its applications. We conclude with suggestions for
future research and developments in this area.