A method of high-powered laser beam welding at least two metallic articles (12,14) by metallurgically joining faying surfaces of the articles (12,14) that are contiguous with oppositely-disposed first and second surfaces (32,34) of the articles (12,14), the method comprising the steps of: placing the articles (12,14) together so that the faying surfaces thereof face each other, a joint region is defined comprising the faying surfaces and juxtaposed surfaces of the articles (12,14) that are defined by portions of the first surfaces of the articles (12,14) adjacent the faying surfaces and remain exposed after the articles (12,14) are placed together, a metallic shim is between the articles (12,14) and contacts the faying surfaces, and an edge portion of the shim protrudes by at least one to thirteen millimeters from the juxtaposed surfaces of the articles (12,14); characterised by: welding the articles (12,14) together by projecting a high-powered laser beam onto the joint region, the laser beam being at a power level of greater than 10 kilowatts and being focused on the juxtaposed surfaces of the articles (12,14) to have a diameter of 0.5 to 1 millimeter at the juxtaposed surfaces of the articles (12,14), wherein the laser beam is unfocused on the edge portion of the shim so that portions (10A,10B) of the laser beam are diffracted by the edge portion onto the juxtaposed surfaces of the articles (12,14), the laser beam and the diffracted portions (10A,10B) thereof melting the juxtaposed surfaces of the articles (12,14), the faying surfaces of the articles (12,14), and the shim and causing flow of molten material at the juxtaposed surfaces and then cooling the articles (12,14) to yield a welded assembly comprising a weld joint entirely through a through-thickness of the welded assembly between the first and second surfaces (32,34) of the articles (12,14), the weld joint defining a weldment surface that substantially coincides with the juxtaposed surfaces of the articles (12,14) prior to the welding step, the weld joint being substantially free of voids between the articles (12,14). placing the articles (12,14) together so that the faying surfaces thereof face each other, a joint region is defined comprising the faying surfaces and juxtaposed surfaces of the articles (12,14) that are defined by portions of the first surfaces of the articles (12,14) adjacent the faying surfaces and remain exposed after the articles (12,14) are placed together, a metallic shim is between the articles (12,14) and contacts the faying surfaces, and an edge portion of the shim protrudes by at least one to thirteen millimeters from the juxtaposed surfaces of the articles (12,14); characterised by: welding the articles (12,14) together by projecting a high-powered laser beam onto the joint region, the laser beam being at a power level of greater than 10 kilowatts and being focused on the juxtaposed surfaces of the articles (12,14) to have a diameter of 0.5 to 1 millimeter at the juxtaposed surfaces of the articles (12,14), wherein the laser beam is unfocused on the edge portion of the shim so that portions (10A,10B) of the laser beam are diffracted by the edge portion onto the juxtaposed surfaces of the articles (12,14), the laser beam and the diffracted portions (10A,10B) thereof melting the juxtaposed surfaces of the articles (12,14), the faying surfaces of the articles (12,14), and the shim and causing flow of molten material at the juxtaposed surfaces and then cooling the articles (12,14) to yield a welded assembly comprising a weld joint entirely through a through-thickness of the welded assembly between the first and second surfaces (32,34) of the articles (12,14), the weld joint defining a weldment surface that substantially coincides with the juxtaposed surfaces of the articles (12,14) prior to the welding step, the weld joint being substantially free of voids between the articles (12,14).