Abstract: An internal combustion engine with a Rankine bottoming cycle including an internal combustion engine (10) with an exhaust (12) for exhausting combustion gases. Included is an expander (24) having a mechanical output (26) for performing useful work and a boiler (18). Liquid is supplied in a line (20) to the boiler to be vaporized therein and the vaporized liquid is supplied by a line (22) to the turbine (24) to drive the same. Heat for vaporizing the liquid in the boiler (18) is obtained from the exhaust (12) on a line (62). The exhaust gases are further expanded in an expander (72) thereby providing additional useful work.