We are both reasonably short, (5'4" and 5'6") but I have mine at 35" above the surface. The higher they are, the more light they cast. Also, if they are clear, you want them high enough so the light doesn't hit your eye so directly. Also, your guests may not be as short as you. Unlike a dining table, you are frequently reaching forward over an island to clean or grab something, and you don't want to be hitting your head on the light, as may often happen at a DR table where it's 30" above the surface.