Public procurement of NBS stimulates innovation by promoting the competitiveness among bidders, who increase the quality of the offer including more value into their proposals. Some benefits are:
- Impulse co-creation on NBS implementation process, by including it as a requisite.
- Foster competition.
- Using a single point of contact for project management.
- Support the development of key NBS performance indicators.
- Promote crossdepartmental exchange .
- Increase NBS network..
- Use pilot projects to build trust in the community.
- Encourage suppliers to think creatively about community engagement.
 

• Political: mature land use management and urban planning, encourage suppliers to think creatively about community engagement
• Economic: inversion in research 
• Social: commitment, environment education, join an NBS network, pilot projects to build trust in the community
• Technical:centres of excelence on NbS procurement, provide policy support to NBS projects, promotion cross-departmental exchange, wide range of technical solutions available for NBS,
• Legal: legal umbrella to stablish green infrastructure and NbS ordinances and regulation, grouping NbS contracts together
   

• Political: lack of commitment, difficult to put together a convincing business case for projects
• Economic: NbS projects might not be prioritised in strict budgets
• Social: negative experiences of engaging with public authorities, lack of trust in city’s commitment to delivering NBS projects
• Technical: The lack of knowledge and experience with NBS among procurement practitioners problems using public procurement to implement NbS projects, widespread confusion between the terms, difficulty to compile universal NBS cost guidelines, lack of the information and/or skills and capacity to apply effective tools and methods to assess the diverse benefits, technical requirements are high, public authorities  report difficulties in finding suppliers willing to bid for NBS projects 
• Legal: lack the political and institutional support to drive forward NBS projects

Manchester engaged with its neighbouring municipality - Salford City Council - to discuss their difficulty in identifying suitable suppliers. Through those discussions, it appeared that  Salford City Council had access to a good pool of landscaping contractors through one of its existing procurement frameworks. It has faced flooding problems with NbS (sponge park).

Wroclaw has enhanced NbS to reduce flooding and heat stress. The condition related to expertise in sustainable rainwater management and design had to be lifted, as it turned out to be impossible to achieve. The formal/financial requirements were lowered to raise the interest of landscaping SMEs. The second call for tender has been successful, however, only one proposal was submitted per demonstrator site.

Glasgow has developed alternative delivery routes to avoid the need to go through its own procurement procedures NBS projects. The parks development and flooding teams regularly collaborate with charities and other public bodies whose procurement powers are less restricted. Promotion of more efficient and effective cooperation between the planning department.

Genoa provided a valuable opportunity for the different municipal agencies and departments to collaborate. Additionally, it has inspired the city administration to include NbS among the requirements for the design of another urban park for the city of Genoa.

Source/Additional information:
European Commission, Directorate-General for Research and Innovation, Mačiulytė, E., Durieux, E., Public procurement of nature-based solutions: addressing barriers to the procurement of urban NBS: case studies and recommendations, Publications Office (2020) Available at: https://data.europa.eu/doi/10.2777/561021

The case studies were collected from European cities, that have procured or are planning to procure NBS (or in some cases NBS planning services). With the exception of one city (Frederiksberg), those NBS projects were supported by the Horizon 2020 funding programme. Information was kindly provided by the municipal representatives of the cities of Manchester, Wroclaw, Glasgow, Turin, Eindhoven, Genoa, Tampere, London, and Frederiksberg, as well as project officers of UNaLab, Clever Cities, ProGiReg, GrowGreen, and Connecting Nature. This information-gathering exercise took place between April 2019 and September 2020.

The DNSH principle is considered as the public procurement considering NBS allows the:

• The protection and restoration of biodiversity and ecosystems
• Climate change adaptation