This master's thesis presents a study on the stability of steel structures under flexural bucklingconstraints. The study focuses on the interaction and behaviour of flexural buckling formulas in SSEN-1993-1-1 and Swedish BSK and the performance of actual structural members subjected to suchconstraints. Numerical solutions were utilized to accurately account for real-world imperfections, suchas initial curvature and residual stresses, which are not fully captured by classical stability theory. Theresearch compares design approaches for beam-columns under axial force and bending momentaccording to Eurocode 3 and Swedish BSK, using five different cross-sections. The resultsdemonstrate that the Swedish BSK method is generally more accurate and easier to understand.However, the accuracy can be further improved by calibrating the exponents in the interactionformulae. This study provides valuable insights into the stability of steel structures and has thepotential to inform the development of more accurate and efficient design methods for suchstructures.