This thesis presents an analytical treatment of surface waves inside a dielectric slab loaded with a conductive and spatially dispersive semiconductor-like substrate. The work is primarily focused on the modelling of the substrate and getting the field solutions out from the Helmholtz equation. Appropriate boundary conditions have been used in order to get a unique dispersion relation. The surface wave modes are then extracted from the relation by using a root-searching algorithm, which in this work is the MATLAB Genetic Algorithm toolbox. Many different substrate configurations have been considered, starting from the very basic isotropic case to the most complex spatial dispersion case. In between, anisotropicity has also been added to the substrate by turning the static magnetic field on. The permittivity tensors are derived from the fluid transport equations and through the course of the thesis, extra terms such as plasma oscillations, damping, cyclotron resonance, and density perturbations are added. Many assumptions, approximations, and limitations of this analytical treatment have also been addressed. Simulations results have been shown to see the effects of these various terms. The substrates analyzed in the chapters are only a theoritical approximation of an actual substrate. The main idea behind this study is to get a feel for how the transport equations can be utilized to obtain properties that might be on a macroscopic scale. The physical significance of this expose has also been discussed in the last chapter. Issues such as scalability to space plasmas and future ramifications are also included. The study done thus far will be useful in investigating such plasma mediums.