A simplified hand method of analysis is presented for the calculation of the overall critical load of planar lateral load resisting structures commonly used to provide stability in tall buildings. They may comprise three stiffness components: bending and shear stiffness in addition to a rotational spring stiffness at the base of the structure. The method requires the calculation of three individual critical loads which are then combined to yield the structural critical load. This allows a rapid assessment of second-order effects on the horizontal displacements and bending moments. The method is most accurate for structures with uniform geometry up the height and is therefore best suited for preliminary stages of design and checking the reasonableness of the results from computer analyses. Copyright © 2002 John Wiley & Sons, Ltd.