Lattice QCD plays an essential role in testing and determining the parameters
of the CKM theory of flavor mixing and CP violation. Very high precisions are
required for lattice calculations analysing CKM data; I discuss the prospects
for achieving them. Lattice calculations will also play a role in investigating
flavor mixing and CP violation beyond the Standard Model.Comment: To appear in Prog. Theor. Phys. Vol. 122, No.1 (Special Issue