A dual cell rear corner pillar for the operator's compartment of a pick-up truck is formed with longitudinally oriented front and rear tubular members. The dual cell tubular construction increases section strength for the rear corner pillar while maintaining packaging constraints for the rear pillar design. The front tubular member is nested against the rear tubular member to provide support therefor longitudinally and vertically. The forward tubular member is welded to the door opening panel seal flange, while the rearward tubular member is welded to the window flange and the back panel flange. The forward and rearward tubular members are also welded to one another to form a strong pillar structure. The dual cell configuration resists buckling and shares loading. The rear tubular member wraps around the front tubular member and transitions into the roof rail area, shortening the unsupported moment arm of the rear tubular member.