Buckling failure occurs suddenly and can lead to the collapse of a structural member withoutany prior warning. The phenomenon is a form of geometric instability, in which a structuralelement experiences deformations and twisting that occur out of the plane of the appliedloads. However, buckling failure can be prevented or limited by bracing the membersufficiently to limit these deformations.The phenomenon is highly correlated to the geometry, boundary conditions, and loadingconfiguration, and it often governs the bearing capacity of the element. The study focuses onthe influence of the elastic lateral restraint and key parameters that affect the lateral torsionalbuckling. The aim of this study is to develop an analytical model to calculate the bucklingload corresponding to the stiffness of the lateral support, as well as other relevant parameters.The motivation for this study arises from the recognition that current building codes do notadequately address the role and requirements of lateral restraints in design practices; instead,it leaves it to design engineers to make their own decisions. The limitations are furtherreflected in structural analysis software, which often treats the restraints as rigid rather thanelastic.The analytical model is derived from the basic concept of the energy method. In order toinclude both the asymmetrical and symmetrical modes of buckling, the Fourier series is usedto express the buckling shape. The Rayleigh-Ritz method of minimising the potential energyand the Numerical mathematical method is adopted to solve the differential equation.The validity of the analytical model for predicting the critical load is assessed by comparingits results with those from the finite element software LTBeamN. Statistical analysis of arepresentative data set indicates a high level of agreement between the analytical predictionsand software results. The analytical model was then utilised in a parametric study, which wasconducted for a doubly symmetric beam with various load and restraint configurations.The study concluded that restraining the compressive flange is the most effective strategy forincreasing lateral-torsional buckling resistance, while the maximum buckling load is achievedwhen the restraint is placed close to the beam’s shear centre. However, achieving thisconfiguration requires significantly higher stiffness. Inaccurate restraint stiffness or improperpositioning relative to the shear centre can therefore lead to an overestimation of the bucklingload. The study also confirms that, in the case of asymmetric buckling, the translation at thenode where the restraint is connected is zero, implying that the load at the lateral restraint isnegligible. Conversely, the force in the restraint reaches its maximum just before buckling,indicating that the lateral support experiences the highest load in this configuration.