The present paper intends to illustrate the main advantages and disadvantages of four alternative seismic deign procedures for concentrically braced frames. In the alternative seismic design procedures additional potentially plastic zones, with reduced beam cross-sections (resembling the „dog-bone” detail), were provided near all girder ends, in order to ensure a larger strength of the columns compared to the frame girders when subjected strong seismic actions. Two six storey concentrically braced frames having two spans of 6.0m and a storey height of 3.5m were design in turn according to the provisions of the in charge European and Romanian seism design codes and according to four alternative seismic design procedures. All structural members (braces, beams and columns) had built up I-shaped cross-sections sized according to the provisions of EN 1993-1-1:2005. All configurations of the concentrically braced frames resulted after the six considered design procedures were subjected to dynamic nonlinear analyses using Vrancea earthquake acceleration records from 04.03.1977, 31.08.1986 and 30.05.1990, calibrated all to a peak ground acceleration value of about 0.3 times the acceleration of gravity. The behaviour of the different designed frames during the dynamic nonlinear analyses was compared. The history of the formation of plastic hinges was observed, the maximum member forces and inelastic deformations, the extreme values of the horizontal displacements and of the base shear forces were compared. The steel consumption was estimated for each concentrically braced frame sized according to a different seismic design procedure.