Public policy is the formal and informal guiding principles that are used by governments and other decision-making entities to guide our everyday lives. Geographic Information Science and Technology (GIS&T) has had an impact on the public policy process since GIS&T’s earliest beginnings in the 1960s. Advances in the development and availability of both geospatial technology and geospatial data paralleled a growing use of data-driven rational planning and decision-making models in policy making at all levels of government. Today more than ever, successful public policy depends on high-quality data and the technology that communicates its meaning effectively. Beyond the rational application of scientific or systematic methods, public policy is about values and how values affect, and are affected by, policies. This requires delivery of credible information in a transparent, understandable form not only to decision makers responsible for adopting policy, but also to various categories of stakeholders whose behavior will be impacted in some way by the policy’s implementation. GIS&T continues to play an important role in that endeavor, including making value conflicts more seeable and knowable. Included in the entry is a summary of the public policy process and its participants, followed by a brief overview of how GIST’s role in public policy has evolved over the last 50 years. The entry concludes by outlining a sample of real-world applications and presenting a discussion of related issues and future considerations.
Public participation geographic information science (PPGIS) has been presented as an alternative to the technocratic methods and tools of GIS. It draws on the generative knowledge practices which emerge when people are clustered together in relation to a decisionmaking practice by intentionally taking part in spatial activities related to the decision. This is a wide context, under which it is important for PPGIS practitioners to reflect on the concepts of “public” and “participation”, adapting their theoretical and practical frameworks to suit the goals and aims of each project. Instead of assuming that including publics will always lead to better quality and more just or democratic outcomes, researchers are encouraged to reflect on the broader geographic and political strategies of involving publics in their work, paying particular attention to building trust and acceptance of PPGIS amongst affected populations. Key to successful participatory GIS is a recognition that whilst everyone is expert in their own lives, conventional practices – including but not limited to those within the spatial sciences – have historically served to privilege specific types of knowledge claim at the expense of others, subjugating the kinds of experiential accounts of place and matter which high-quality PPGIS is able to generate.