The convection-diffusion equation is present in the formulation of many petroleum reservoir engineering problems. A representative example, the tracer injection problem, is solved analytically here, through the generalized integral transform technique so as to illustrate the usefulness of this approach, for this class of problems. Classical assumptions, such as steady-state single phase flow and unit mobility ratio, are adopted, Comparisons with alternative analytical (when available) or numerical (finite difference) solutions are performed and benchmark results are established.