The buckling strength of conical shells subjected to axial compression may be increased by means of meridional stiffeners (stringers). Unlike stiffened cylinders, only limited research has been carried out and no design provisions exist for stringer-stiffened cones. In this paper, a design procedure for such cones is developed based on an equivalent cylinder approach. Design criteria for both local (shell panel) and global (stiffened panel) buckling modes are proposed. In the absence of experimental results, a numerical parametric study is then presented to assess the design proposal. By using finite-element models, linear and nonlinear analyses are performed to quantify critical design aspects and to calibrate buckling strength predictions derived from the design proposal.