Depending on a number of variables — climate, back-up construction, form — stucco can be applied without control joints. This house is covered in various materials, including Ipe wood (bottom left) and HardiePanel siding (center), but note how the stucco at the top left and at the right uses vertical and horizontal control joints to break up the expansive walls, bringing the scale closer to the other surfaces. The lines relate to the windows, a way of anchoring them to the stucco, rather than having them appear to float.