Accurate Monte Carlo calculations of the surface tension of liquid arg
on, krypton and xenon near their triple points are described. Reliable
pair potential functions are used and calculations are made both with
and without the Axilrod-Teller-Muto three-body interaction. A novel p
erturbation method is used for the calculations with three-body intera
ctions. Pair potentials alone give values of surface tension which are
larger than the experimental values by 19% for argon and by 35% for x
enon. When the three-body interaction is included the calculated resul
ts are within 2.2% of the experimental values for argon, krypton and x
enon.