Offshore renewable energy structures, such as wind turbines or tidal turbines, might use suction caissons as foundations. One of the key processes is the design for the installation as this is where substantial cost savings could be made. A number of different approaches for assessing the installation suction, and other associated installation parameters, are available but no common standard has yet been agreed. For the technology to be widely employed, robust installation behaviour must be demonstrated, and must be shown to agree with the different approaches proposed. The soil conditions around the UK vary significantly, ranging from homogeneous sand and clay, through to complex layered materials.A recent research project, carried out at Oxford University, has explored suction caisson installation behaviour for a range of these different site conditions (Cotter, 2009). This will enable designers to assess where caisson foundations are appropriate and also where they are not. This paper provides a summary of the outcomes from that project and more details can be found in Cotter (2009). Initially, dimensional analysis was carried out to determine the key dimensionless groups controlling the problem. The experimental work was designed, using these dimensionless groups, to be representative of full scale behaviour at a range of sites around the UK coastline.