Concern has been expressed about the safety and serviceability of various forms of grandstands when subjected to human loading, particularly loading which is synchronised and periodic as may occur at some pop concerts. This paper gives details of the main results obtained from BRE full-scale tests on permanent cantilever grandstands. The dynamic behaviour of the empty stands in terms of their natural frequencies, damping values and mode shapes are presented. The results from ten stands that were monitored during live events are also presented in terms of the peak accelerations obtained, and the changes in the dynamic characteristics that occurred as the stands were loaded. This paper will be of interest to those engineers who are responsible for designing stands or for local authority licensing of stands. 8 pages.