"The purpose of this research was to develop novel laser welding methods to improve the quality and performance of thin-sheet metal joints. Dual-beam laser welding of aluminum and laser welding of zinc-coated steel were performed. A pulsed Nd:YAG laser was used as the welding laser while an auxiliary continuous wave diode laser was used as a pre-heating source in lap welding of two 50-[Mu]m aluminum sheets. The weld quality was then examined under scanning electron microscope and evaluated using micro-indentation hardness tester. Results show that deeper weld penetrations and higher tensile strengths were obtained using the dual-beam laser welding technique when compared to that of single beam Nd:YAG laser welding. Joining of zinc-coated steels has proved to be a challenging problem because of the vaporization of low boiling temperature zinc during the welding process resulting in a number of weld defects. A ""Vent hole"" approach, in which the 0.68 mm (24-gauge) galvanized steel sheets were pre-drilled using a pulsed Nd:YAG laser and then welded in lap-joint configuration using a 1.5 kW continuous wave CO2 laser. With the addition of vent holes, zinc vapors were able to escape through the weld thus reducing weld defects such as porosity, spatter, and loss of penetration. The quality of the welds was inspected under optical and scanning electron microscopes and the properties were determined by tensile/hardness tests. Results are compared with those obtained in the conventional procedure of a constant joint gap between the sheets. The study revealed that novel techniques further enhance the capabilities of lasers in thin-sheet metal welding useful for automotive, electronic and consumer industries."