Analytical solutions that describe the elastic-plastic behavior of a beam column loaded at the ends and the midspan are presented. Much work has been done on the elastic solution, so the current effort is to extend this work to the inelastic range. Difficulties associated with the analysis are outlined, and the method of attack in overcoming these difficulties is described. The theoretical analysis of the six different cases which correspond to different stages of plastification wihtin the beam column is analyzed. Interaciton curves for combinations of axial force and lateral load that can be safely supported by the beam column of rectangular and wide-flange cross-sections are presented.