A system for controlling pile orientation comprises a pile (14) and a pile guide (20) for supporting the pile as it is driven into a substrate, the pile guide comprising a base frame (10) and a pile guide member (22) mounted on the base frame. The pile (14) and the pile guide member (22) have slidaby interengaging profiles (30, 40) comprising first and second parts (32, 42), which are configured to axially rotate the pile to correct any misorientation relative to the pile guide as the parts slide past each other, and third and fourth parts (34, 44), which are configured to maintain a predetermined orientation of the pile relative to the pile guide once any misorientation has been corrected by interengagement of the first and second parts.