  We study the distorted wave renormalisation group (DWRG), a tool for
constructing power-counting schemes in systems where some diagrams must be
summed to all orders. We solve the DWRG eqaution for a variety of long-range
potentials including the Coulomb, Yukawa and inverse square. We derive
established results in the case of the Yukawa and Coulomb potentials and new
results in the case of the inverse square potential. We generalise the DWRG to
systems of three-bodies and use it to find the power-counting for the
three-body force in the KSW EFT. This power-counting corresponds to
perturbations in the renormalisation group about a limit-cycle. We also derive
equations for the LO and NLO KSW EFT distorted waves for three bosons and for
three nucleons in the neutron-deuteron spin 1/2 channel. The physical results
in the nuclear system agree well, once the LO three-body force is determined,
with predictions of more sophistocated potential models.
