I participated in an expert meeting entitled “Sharing experiences and finding practical solutions regarding the implementation of the United Nations Guiding Principles’ effectiveness criteria in grievance mechanisms”...organised by ACCESS Facility...[T]his post offers a few preliminary reflections on two recurring questions: Why is measuring the effectiveness of grievance mechanisms important How can effectiveness be measured?...A few companies are taking the lead in measuring the effectiveness of their mechanisms...Anglo American started “measuring the effectiveness of the group-wide mechanism on the basis of key performance indicators … in 2011”. This is good news...[V]alid measures of the effectiveness of GMs are fundamental to convince those who are sceptical about non-judicial remedies. The risk is that the very idea of GMs will be written off because so many of those that exist are not trusted. This is important to know that GMs work. This is important to know which GMs work better.