Gives a base for computing stresses in crane structures and permissible stresses for steels to BS 4360. Covers classification based on severity of intended use of load to be considered, selection of steel, minimum thickness of plates and sections, working stresses, basic stresses in joint fastenings, web plates and stiffeners and fluctuating loads. Appendices give classification, use of steels of higher tensile strength than those to BS 4360, effective lengths of jibs, basic formula, design checks, and fatigue strength of structural components.