Design measures for providing earthquake resistance in high rise buildings are set out. It is essential that any building designed to code seismic coefficients should have adequate ductility, since its structure will be forced well into the yield range in a major earthquake. Methods of assessing the ductility requirements in individual members of building frames are presented, together with procedures for determining the values of ϕu /ϕy at individual hinge points, under seismic deflections into the plastic range. Conditions which give rise to large values of ϕu / ϕy are pointed out. Design problems involved in the formation of column hinge s are dealt with. Considerations affecting the use of dynamic analysis for elasto-plastic response in determining values of ϕu /ϕy at hinges are pointed out. Design procedures for satisfying ductility demands in individual members are discussed.