The Scheldt Plains Nature Park (in Wallonia) and the Scarpe-Escaut Regional Nature Park (France) have a common desire to strengthen their cooperation through the Hainaut Cross-border Nature Park (PNTH). The PNTH Terre en Action (Earth in Action) project aims at the implementation of collective approaches carried out by the inhabitants and the stakeholders of the cross-border territory around natural and landscape heritage. This project takes the shape in particular of the launch of a calls for projects, the support of citizen initiatives, and the organisation of cross-border events to promote the territory’s heritage and resources. The pooling of tools and the development of adapted methodologies on both sides of the border enable the enrichment of actions that will be implemented with the inhabitants.