  The main theorem of this paper classifies the quasi-geodesics in a Coxeter
group that are tracked by geodesics. As corollaries, we show that if a Coxeter
group acts geometrically on a CAT(0) space X then CAT(0) rays (and lines) are
tracked by Cayley graph geodesics, all special subgroups of the Coxeter group
are quasi-convex in X, and in Cayley graphs for Coxeter groups, elements of
infinite order are tracked by geodesics.
