Hybrid laser-MAG welding experiments were carried out to investigate the effects of process parameters on weld shape and the relationship between weld shape and weld strength. The experiments included butt joints with full penetration and butt joints and fillet joints with partial penetration. The effects of wire feed speed and gap width on weld cross-section were investigated. The effects of root shape at different gap widths on joint mechanical properties were determined. The use of chamfers to reduce gap sensitivity was investigated.