Abstract: A foot rest (10) for supporting the feet of a boater in a boat such as a canoe or kayak. The foot rest (10) is movable along the length of the boat such that boaters having longer or shorter legs than others may be accommodated while requiring only one adjustment. The foot rest (10) includes a mounting rail (12), a foot support block (14), and a retainer rail (16). The mounting rail (12) is a linear member and is disposed along the longitudinal axis of the boat in front of a seat. The mounting rail (12) may be formed separately from and secured to the boat. The mounting rail (12) defines a plurality of indexing receptors (24) opening on the top side thereof for receiving cooperating indexing members (30) carried by the foot support block (14). The foot support block (14) includes a pair of foot engagement pads (26) carried at either end of a bridge (28). The indexing members (30) are configured to be closely received by and cooperate with the indexing receptors (24) defined by the mounting rail (12).