Residual stress and distortion continue to be issues in shipbuilding despite the large amount of research carried out in this area.  This paper demonstrates how the welding process has a significant impact on the measured distortion.  The shipyards currently use submerged arc welding and this process is compared with DC gas metal arc welding, pulsed gas metal arc welding, Fronius Cold Metal Transfer (CMT), laser and laser hybrid welding on butt welds in 4mm thick DH36 ship plate.  Laser and laser hybrid welding clearly produce the lowest distortion.  Nevertheless a considerable improvement can be achieved with the pulsed gas metal arc welding and CMT processes.  The paper seeks to understand the relationship between heat input, fusion area, measured distortion and the residual stress predicted from a simple numerical model.