Bridges can be excited by the action of wind, vehicles, or pedestrians. Whereas there are well developed methods to calculate dynamic behaviour, there have been comparatively few correlations with full scale measurements. The Transport and Road Research Laboratory has therefore undertaken a programme of research to measure the response of selected bridges to such loading. The work has also included tests in which the bridges were excited by an energy input device and damping values were measured from free decays. Response to wind has been measured for two steel box girder bridges having orthotropic decks. Automatic self-switching equipment was used to record bridge acceleration, wind speed and direction, when wind speeds exceed a threshold level. Response to traffic has been measured for a multi-span steel box girder viaduct having a concrete deck. Response to pedestrians has been measured for a variety of types of footbridge. Measured values of bridge response are compared with calculated values using procedures recommended in the new British Design Standard./Author/