Abstract: An inflatable boat for high speed towing applications having a compartmentalized hull and an improved tow-ring mounted beneath the hull, the hull including first and second buoyancy chambers, the second chamber being vertically disposed beneath the first chamber. Inclined, flexible reinforcing partitions are substantially vertically disposed within the second buoyancy chamber to substantially divide the chamber into a plurality of sub-chambers, and restrain the bottom wall of the chamber upon inflation, to form outwardly projecting convex arcuate portions having longitudinal grooves defined therebetween. The tow-ring includes a reinforced hollow structure having interior reinforcing walls and a convexly curved top wall, portions of the walls together defining a peripherally disposed pair of longitudinal tie-line tunnels and a transverse tie-line tunnel, sized to receive a tie-line therethrough.