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A numerical investigation regarding ductility evaluation of steel buildings with moment resisting steel frames is conducted. Bending (&micro, Lϕ) and tension (&micro, L&delta, ) local ductilities as well as story (&micro, S) and global ductilities are studied. Global ductility is calculated as the mean values of story ductilities (&micro, GS) and as the ratio of the maximum inelastic to yielding top displacements (&micro, Gt). The ductility capacity is associated to drifts of about 5%. Ductility values significantly may vary with the strong motion, ductility definition, structural element, story number, type of analysis, and model. &micro, Lϕ is much larger for beams than for columns. Even though the demands of &micro, are considered an important issue they are less relevant than &micro, Lϕ. &micro, S is much smaller than &micro, Lϕ for beams. &micro, GS for dynamic analysis give reasonable values, but &micro, Gt does not. &micro, Lϕ, &micro, S and &micro, GS obtained from pushover are larger than those obtained from dynamic analysis and unlike the case of dynamic analysis, &micro, Lϕ tend to increase with the story number showing an opposite trend. Considering that: &micro, Gt for dynamic analysis results in unreasonable values, pushover analysis does not consider energy dissipation, the strong column&ndash, weak beam (SCWB) concept was followed in the model designs, and &micro, is not relevant in framed steel buildings, the ratio (RLG) of global to local ductility capacity is calculated as the ratio of &micro, GS to &micro, Lϕ of beams, for dynamic analysis. A value of 1/3 is proposed. Thus, if bending local ductility capacity is stated as the basis for the design, the global ductility capacity can be easily estimated.