A method of laser welding structures having different steel grades together. The method includes providing a first structure made from a first steel grade and composition and providing a second structure made from a second steel grade composition. The first structure is positioned adjacent the second structure to create a weld zone area wherein at least a portion of the first structure overlaps at least a portion of the second structure. A filler material is selected that has a composition that will create a weld joint between the first structure, the second structure and the filler material such that the weld joint has a predetermined microstructure. The filler material is positioned adjacent the weld zone area. A laser beam is directed at the weld zone area to create a weld joint between the first structure, the second structure and the filler material, wherein the weld joint has a predetermined microstructure.