Polarization is a complex phenomenon. Studies in polarization phenomena clearly indicate that it is the physical behavior of material dipoles in various anisotropic crystalline media that dictate the observed results. Isotropic bulk material can support the propagation of multitudes of different EM waves of many different frequencies and polarizations through the same volume unperturbed by each other. The chapter shows that a careful observation and analysis of superposition effects due to multiple superposed waves possessing different states of polarizations should help reveal whether fields sum themselves or a stimulated dipole sum the joint stimulations to display the superposition effects. Polarization of reflected light by the boundary surface and the related Brewster angle indicates that even the dipolar oscillations of boundary molecules, in otherwise isotropic media, are constrained in their dipolar undulations by the abrupt physical changes in the boundary layers of media.