Large basis set ab initio calculations have been carried out for a den
se grid of points on the He-3 potential energy surface. Three-body con
tributions were extracted at every point, and a number of concise func
tional representations for the three-body potential surface were then
examined. Three-body multipolar dispersion terms and other radial and
angular terms were used in the representations, and an assessment of r
elative importance of the different terms is presented. Combined with
a two-body He-He potential, the results of this work should offer a hi
gh quality interaction potential for simulations of aggregated helium.