Generalized impedance boundary conditions are derived for a planar, homogeneous, magnetic dielectric slab grounded by a perfect electric conducting plane and for a magnetic dielectric coated, perfect electric conducting circular cylinder. By invoking the duality principle, generalized resistive boundary conditions are also obtained for a planar, transparent dielectric slab. In the method followed here, it is not necessary to have a prior knowledge of the Fresnel reflection and/or transmission coefficients of the configuration under study to obtain the generalized boundary conditions. The boundary conditions developed here for the planar slab recover the exact Fresnel reflection and transmission (for the transparent slab) coefficients. Finally, the boundary conditions for the coated cylinder are used to obtain a solution for the scattering of an obliquely incident plane wave field, and this result is compared with the exact solution.