Large-scale projects typically address national or regional needs rather than local interests. These projects include public infrastructure for transport, energy, or large public facilities but may also be initiated by private stakeholders such as for industrial or tourist purposes. Switzerland’s federal system involves multiple levels of authorities taking decisions in various phases of realizing projects such as in the design, in planning and implementation, or around public funding. The legal framework around spatial planning, public funding and construction permits creates arenas for local interests to be taken up at all stages of a large-scale project. The chapter aims to highlight how local participatory processes are shaped by national and cantonal frameworks and what arenas and processes exist for local interests to influence the decision-making on large-scale projects in Switzerland. The chapter concludes that in Switzerland local interests are not only playing a role in local governance processes but also regularly feed into political processes at higher levels. The participatory processes are perceived as relatively successful in bringing in new facts and clarity about the varying views and positions of different stakeholders, including those of locals, and allow for a more solid balancing of interests by the decision-makers at all levels.