The theory of stationary optics, which has recently been developed for guided waves in dielectric waveguides, is briefly reviewed. The various rules for the stationary rays, called the wave-normal rays, are discussed in comparison with the conventional dynamical optics rules. However, our attention is restricted to the simplest example of applications to illustrate the basic idea of new geometrical optics. Mathematical details of derivation are omitted. ¿ American Geophysical Union 1993