Pressure variations and 3D effects on liquid sloshing loads in tanks have been carried out experimentally. Recently, considerable advances have been made in the development of numerical techniques for studying the liquid sloshing on large structures. However, there is a lack of high quality experimental data that may be used for validating the analytical and numerical solutions obtained. This paper describes the results of the research project conducted at the Hydroulics Laboratory of Civil Engineering Faculty of Istanbul Technical University. The primary objective of the project is to investigate the pressure distributions at different locations and 3D effects on liquid sloshing. In this purpose, an experimental setup is designed to study the non-linear behavior and damping characteristics of liquid sloshing in partially filled 3D rectangular tank. Both several configurations of baffled and unbaffled tanks are studied. (c) 2005 Elsevier Ltd. All rights reserved.