The buckling problem of thick, cross-ply laminated cylinders and cylindrical panels under combined external loading is investigated on the basis of fully three-dimensional elasticity considerations. The three-dimensional pre-buckling stale that is initially employed, assumes zero shear stresses and is suitable for the analysis of both open panels and closed cylinders. This assumption leads to a set of three-dimensional linearized buckling equations. Both sets of three-dimensional prebuckling and buckling equations are then solved on the basis of a recursive method. The analysis is suitable for studying the buckling behavior of simply supported cross-ply cylinders, subjected to the single or the combined action of an axial compression and a uniform lateral pressure, or open cross-ply cylindrical panels under axial compression. The numerical results presented and discussed throughout this paper deal with cylinders and cylindrical panels having a symmetric or an antisymmetric cross-ply lay-up.