  The calculation of the finite lattice spacing corrections for I=2 pi-pi
scattering is carried out for isotropic and anisotropic Wilson lattice actions.
Pion masses and decay constants are also determined in this context. These
results correct the phase shift calculated from the lattice, which is connected
to the scattering length and effective range in this low energy scattering
process. When in terms of the lattice-physical parameters for either Wilson
action, these lattice spacing effects first appear at the next-to-leading order
counter-terms.
