Cities and regions in Europe (EU) and Community of Latin American & Caribbean States (CELAC) face shared and urgent global-local challenges to integrate practical actions with strategies to achieve greater inclusion, biodiversity, climate change adaptation and environmental quality. Many cities share problems of landscape fragmentation caused by rapid growth, urban sprawl and economic restructuring. Poorly planned urbanisation leaves a legacy of cities lacking the green areas needed for ecosystems to provide the services essential to human life. Nature-Based Solutions (NBS) have the potential to help reverse these trends, and our combined EU-CELAC palette of socio-cultural, ecological and governance contexts represents a huge opportunity to move forward - faster, together. CONEXUS will co-produce, structure and promote access to the shared, contextualised knowledge needed to support cities and communities to co-create NBS, and to restore urban ecosystems, to help drive the required step-change in urban policy and practice in EU and CELAC countries. It adopts a planetary health perspective: healthy landscapes and ecosystems are vital to support human life, and humanity must restore, create and care for these landscapes and ecosystems in a reciprocal, ongoing and iterative relationship. This transdisciplinary project uses nature-based thinking (NBT) to bring together community, private, public and research partners to meet this challenge, and experiments with novel co-production methods to deliver NBS innovations in ‘Life-Lab’ pilots. The project’s core concept is to co-create context-appropriate NBS for ecosystems restoration and sustainable urbanisation in CELAC and EU cities, using a place-based approach (place-making, place-keeping and place-prescribing), solving problems together with citizens. The CONEXUS cities are: in CELAC - São Paulo, Bogotá, Santiago and Buenos Aires; and in the EU - Lisbon, Barcelona and Turin.