CLEARING HOUSE Knowledge Exchange Mechanism
The global objective of the knowledge exchange mechanism is to promote capacity development and exchange of knowledge and practices on urban forests as nature-based solutions (UF-NBS), based on peer-to-peer exchanges and scientific support regarding UF-NBS challenges.
This exchanges will tackle one or several of the following themes, as a focus of the project:
- inner-city afforestation
- air quality improvement
- socio-cultural integration
- green infrastructure
The knowledge exchange mechanism is composed of two paths: the City Tandem and the Task Force.

About the City Tandem
The City Tandem aims to foster international links at the local level, enabling local leaders to gain new perspectives on UF-NBS.
Local authorities (cities, metropolises or regions) wishing to exchange with another local administration facing similar challenges on planning and managing urban forests are encouraged to apply to take part in a CLEARING HOUSE-supported City Tandem.
About the Task Force
The global objective of the Task Force is to offer the opportunity to a selected local authority to receive scientific support regarding UF-NBS challenges from the CLEARING HOUSE experts partners.
This support will include a review of the challenge stated, research for gaining more in-depth insight in the challenge in the specific territory of the local authority, and an action plan for implementing the suggested solutions.
More about the Knowledge Exchange Mechanism technicalities
Participating in the City Tandem is an opportunity for local authorities to foster capacity development and exchange of knowledge and practices on concrete urban forests as nature-based solutions while receiving support from experts of the CLEARING HOUSE project.
Participants will:
- Explore solutions and innovation provided by UF-NBS peer cities, and learn how to adopt them.
- Get support from recognized international experts and academics.
- Showcase local governments experiences, policies and good practices internationally.
NB: For the City Tandem, representatives of the selected local authorities will receive a travel grant to visit their city partner and get to know their UF-NBS project(s) on the ground.
Any local or metropolitan authorities located in Europe or East Asia committed to the implementation of UF-NBS projects and with a population of :
– 250.000+ inhabitants for the City Tandem
– 50.000+ inhabitants for the Task Force
NO CALL CURRENTLY OPEN.
For any local authorities wishing to participate in the call for interest in the Task Force, official representatives of this authority must send the following required documents to Mr. Guillaume Berret gberret@metropolis.org (subject: CLEARING HOUSE TASK FORCE) :
- Application form
- Letter of participation stamped and signed by an official representative of the local authority wishing to participate
- Any documents (or link to webpage) supporting the commitment of the local authority to the implementation of UF-NBS projects in its territory (Action Plan, Projects, Budgets…)
An ad-hoc Selection Committee, formed by partners in the CLEARING HOUSE project will select a local authority proposals.
The following criteria will be considered by the committee during the selection process:
- Level of commitment, degree of implementation of UF-NBS programmes/projects – proved by any documents relating to the implementation in the local authority represented (Action Plan, Budget…)
- Involvement of the local authority in another H2020/EU project tackling UF-NBS or other nature-based solutions.
- Contribution of submitted UF-NBS project/s to the accomplishment of goals established by the global agendas (2030 Agenda for Sustainable Development, the New Urban Agenda, the Paris Agreement on Climate Change, Sendai Framework for Disaster Risk Reduction, Aichi targets…)
- City administration whose mayor/highest political representative will be in office between March 2023 through December 2023, period of implementation of the City Tandem
- Accordance to the UF-NBS to the IUCN Global Standard on NBS or willingness to participate in the IUCN Urban Nature Index program
- Geographical balance in the final selection
- Topic submitted matches to the one of a potential city partner (only for the City Tandem applications)
A look back at our 1rst Knowledge Exchanges

In 2022, Bogotá, Mexico City and Belo Horizonte were selected within the framework of the 1st call for the knowledge exchange mechanism.
Mexico City and Belo Horizonte, which were selected to form a City Tandem, decided to exchange on inner-city afforestation and green infrastructures as it represents a current challenge in their cities.
Bogotá, which was selected to receive the help of the CLEARING HOUSE Task Force, chose to receive feedback and recommendations by CLEARING HOUSE experts on the review of its new Urban Forestry Policy and its Implementation Plan, a new policy intended to establish guidelines for the implementation of Urban Forests in the Capital District of Bogota.
More about the outcome of the first knowledge exchange mechanism here.