Increases in lightness and slenderness of footbridges have brought new design requirements. Despite the small loads associated with pedestrian action, two landmark projects, the Millennium Bridge in London, and the Solfrino Bridge in Paris, have shown the importance of human-induced vibrations and dynamic effects in long span footbridges and given rise to new methodologies for their assessment and control. This has sparked intensive research, and the development of new numerical and experimental tools for assessing and controlling pedestrian effects, and new design guidelines and recommendations.