The behavior of moment connections and beam-column joints in moment resisting steel frames subjected to severe earthquakes is studied. The cyclic inelastic deformation capacities of different types of connections are discussed and design recommendations are presented that are intended to assure the development of plastic hinges in beams at the column faces. A conceptual approach to the prediction of the low cycle fatigue life of welded connections under random loading is outlined, utilizing concepts of elastic-plastic fracture mechanics. The shear behavior of beam-column joints subjected to large cyclic beam moment reversals is summarized. Based on experimental evidence and a simplified mathematical model for shear strength, a method for the shear design of joints is proposed that should permit a reduction in the demand for shear stiffeners in joints.