Bouwmeester, JosjeJosjeBouwmeesterAy, DenizDenizAy0000-0003-3927-2903Gerber, Jean-DavidJean-DavidGerber0000-0001-9111-9071Hartmann, ThomasThomasHartmann2025-12-102025-12-102025-11-11https://boris-portal.unibe.ch/handle/20.500.12422/224121One of the difficulties in implementing densification objectives is that planners often do not have sufficient coercive power to restrict property rights, which means that landowners can resist the implementation of land use plans. As a result, planning increasingly takes place on the project level, allowing planning authorities and developers to renegotiate the terms and conditions of densification. While project-level negotiations have been researched, these studies do not focus on individual landowners but rather on developers. This article examines how developers and public authorities manage the property rights of individual landowners to prevent delays or blockages in project implementation. Drawing on a comparative case study of Thun (Switzerland) and Utrecht (Netherlands), we show how project-based planning takes different forms depending on legal frameworks and planning norms. In Thun, strategies focus on consensus building and input legitimacy; in Utrecht, more coercive instruments such as expropriation are used and legitimized based on their output. The findings suggest that project-based planning tends to exclude individual landowners from negotiation, framing their objections as obstructions to be managed. While individual owners’ interests are often sidelined, the private economic interests of developers and large landowners often appeal to collective goals such as climate change mitigation or housing supply. This raises broader questions about which interests are recognized, or dismissed, in the construction of social sustainability in urban densification.endensification planning negotiationsproject-based planningproperty rightssocial sustainability900 - History::910 - Geography & travelarticle10.48620/9261810.1177/00420980251379767