This working group brought together, for nearly 4 years, 28 experts representing 18 OECD countries. The Objectives of this group were: First it was to Review the latest research works in the field of motorcycling safety; Notably in order to Better understand the mechanisms and the configurations of traffic crashes; And it was also to Evaluate the most effective measures to prevent and mitigate these crashes in the frame of a 'safe system' approach; And at the end the purpose was to Make recommendations to decision makers