This lecture covers the formation of residual stresses during welding, methods of distortion control, typical defects in weld joints, failure of weld joints, mechanical aspects of brazed joints, potential solutions to reduce thermal stresses, considerations for braze joint geometries, typical defects in braze or solder joints, effects of constrained plastic deformation, failure of braze and solder joints, mechanics of lap joints, and considerations for braze joint geometries. Additionally, it explores catastrophic failures of joints and introduces metal additive manufacturing, including laser powder bed fusion, electron beam melting, directed energy beam deposition, wire fed directed energy beam deposition, and 3D binder jetting. The advantages, disadvantages, applications, and key aspects of each metal additive manufacturing technique are discussed.