cColumn is a powerful Windows program designed specifically for structural engineers to perform axial-flexural analysis and design of concrete columns, as well as beams and shear walls, according to ACI 318-14/11/08/05/02 and ACI 318-99. It analyzes the uniaxial or biaxial bending capacity of multiple sections of regular shapes (rectangular, round, Tee, I, L) and generic shapes (with openings) simultaneously in an accurate, fast, and user-friendly manner. Multiple load sets may be inputted and checked against section capacities. It features tabulated strain-P-M at every user defined neutral axis step, 2D P-Mx and P-My interaction diagrams, and incredible 3D P-Mx-My interaction surface. It is built upon OpenGL(R).