This document summarises insights from a peer learning workshop in Basel, Switzerland in June 2023. The workshop explored best practices in anti-corruption Collective Action initiatives. The report covers:

1. The role of the facilitator in Collective Action initiatives. 
2. The different roles that representatives from the private sector, public sector, civil society and academia play.
3. The process of establishing a Collective Action initiative and securing funding for it.
4. Ways to monitor progress and evaluate impact.

It ends by emphasising the importance of continuing to learn from one another and to share information, including by contributing to the B20 Collective Action Hub.

The peer-learning workshop and the preparation of this short report were funded by the Siemens Integrity Initiative.