The control of the group velocity dispersion (GVD) in the waveguiding structures may be of crucial interest in optical communications. It may be achieved controlling one of the components of GVD, the waveguide dispersion, which depends on the geometry and the refractive index profiles of the guiding structures. In this paper the waveguide dispersion in practical guiding structures is evaluated by means of a general numerical procedure, based on a FEM formulation and a second order perturbation of the corresponding eigenvalue equation. The evaluation is performed for various values of geometrical and physical parameters of the guiding structures, in order to seek for a best structures configuration, in which waveguide dispersion may compensate the dispersive effects of the optical materials in a given frequency range. Particular attention has been devoted to the possibility to control the sign of GVD in the single mode region which is of great concern for the design of all optical components.