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This study develops and experimentally validates an innovative technique for enhancing the seismic performance of steel beam to column moment connections. The technique involves reducing the strength of specified regions of the beam flanges by exposing them to high temperatures followed by slow cooling. Analogous to the reduced beam section (RBS) connection, yielding and plastic hinge formation is promoted in the heat-treated beam section (HBS). Moreover, because the elastic and inelastic modulus of the steel is unmodified by the heat-treatment and the beam cross section is not altered, an HBS connection does not sacrifice elastic stiffness or buckling resistance as does the RBS. Design of the HBS connection was performed through detailed finite element analysis and material testing. Two large scale connections modified with the HBS technique were tested in this study. The test program showed that the proposed heat-treatment technique was successful in the promotion of yielding and plastic hinge development in the heat-treated regions with specimens attaining interstory drifts as high as 6% without weld or near weld fracture. Strength degradation due to beam buckling within the HBS was the observed failure mechanism in both specimens. Detail analyses of strain and beam deformation data are presented to explain the HBS connection plastic hinge formation and gradual strength degradation. Broader applications of the technique to other structural components are identified.