Goal: Locate and list all the relevant actors for the construction and/or biomass sector in your city. This data will enable cities to determine who and where the actors are, but also to identify if crucial circularity actors are missing from the territory which can assist them in policy making and planning future actions.

Remember that QUALITY is more important than QUANTITY. Find out who is really most relevant and those are the actors that you should list. Try to do this for all economic activities and the sector materials.


  1. Ask yourself: What are key organisations within my city related to the sector? These could be large companies that play an important role in material stocks and flows, but it could also include academic institutions that research these matters, municipal departments that govern these topics, utility companies, industry associations, research groups, or activist organisations.
  2. Create a spreadsheet with the following columns: Organisation name | Website | E-mail | Contact person (if applicable) | Relevant materials | Relevant topics | Comments/notes
  3. Add all the actors to this spreadsheet.
  4. Once you are done, upload this list and tag it with the “ACTORS” tag (remember to mark yourself as author, and to give this a creative commons licence).


  • Finding the actors will help you later on to know who could have data on material flows and stocks. If you already come across this information during this search, be sure to make a note of and hold on to it.
  • If you are using data from the chamber of commerce, be sure to use the best of your knowledge: just because a business is registered in the city, it doesn’t mean that they do business in that city!

The concept of actors is thoroughly explained in this video, along with valuable information on where to find examples of actor lists.

Outline of the video

  • The video discusses the importance of knowing the actors involved in the sector-wide circularity assessment. Actors refer to companies involved in specific sectors and materials.
  • M0:53-1:46 Overview of company information and all of the actors that exist per NACE codes (classification system) and materials.
  • M1:46 Where you can find this type of information. The Chamber of Commerce is a potential source of information on companies. (e.g. in the Netherlands it’s the “Kamer van Koophandel”
  • M2:11 Metabolism of Cities Data Hub provides examples of documented actors, emphasising the need for collaboration to achieve circular flows,