Liquid sloshing in a cylindrical tank with various fill levels and ring baffles under the excitations of roll motion is experimentally investigated. The primary objectives of the experimental study are to examine the relative effectiveness of various baffle arrangements, to provide test data for the verification of the numerical models and to recommend a practical baffle arrangement that would be effective over a range of frequencies. For these purposes, an experimental setup is designed to study the non-linear behaviour and damping characteristics of liquid sloshing in a partially filled cylindrical tank. Both several configurations of baffled and unbaffled tanks are studied and the rolling angle, the filling depth and the rolling frequency are changed systematically. It is found that ring baffle arrangements are very effective in reducing the sloshing loads. (C) 2012 Elsevier Ltd. All rights reserved.