Corruption in state-owned enterprises has a unique ability to undermine governments, markets and citizens’ well-being. While international standards promote integrity in the state-owned sector, their implementation remains a challenge. This handbook describes an innovative peer-learning programme – Compliance Without Borders – and its contributions to strengthening anti-corruption compliance in state-owned enterprises. It explains the benefits of galvanising the private sector to work with their state-owned counterparts in preventing corruption and levelling the playing field. By detailing how this new pair are successfully collaborating through Collective Action, the handbook also encourages others to join in leading by example.