The paper is divided into four sections, each dealing with a specific aspect of the current research program in the Department of Electrical Engineering at Sheffield University. Section I deals with the radiation from a cylindrical surface-wave resonator. Section II presents some numerical results obtained by an electronic computer of the guide-wavelength/dielectric constant relationship for the

mode on a dielectric rod. Section III deals with the coupling between two adjacent surface waveguides. Parallel dielectric sheets and parallel rods are both discussed theoretically. Section IV presents the theory of a new form of surface-wave launching antenna, including an evaluation of its hunching efficiency.