The previous two chapters have discussed different sources of data that are central to developing revitalization initiatives. Public participation is another source of local knowledge as well as a critical process for ordinary residents to engage with proposed projects and discuss shared concerns. Public participation can be considered democracy in practice because it provides regular people with the opportunity to be involved in day-to-day decisions that affect them (Beierle and Cayford 2002). As Diane Day (1997) has argued, however, public participation is “an essentially contested concept.” Although it is good for its own sake and necessary in a democratic society, participation can be at odds with planning practice. Instead, planning is often driven by local politics, technical expertise, and professional knowledge (including those tools discussed throughout this book).