In this paper the influence of transverse shear deformation and rotatory inertia upon the flutter load of Beck's column with various support characteristics for a variety of slenderness ratios and cross-sectional shapes is presented. The analysis is based on Cowper's formulae for establishing Timoshenko's shear coefficient K'. From this investigation it is found that the inclusion of these parameters may have an appreciable destabilizing effect in the case of a fully fixed cantilever, and particularly in the case of a partially fixed cantilever with an attached mass at the support. This occurs especially in columns with low critical slenderness ratios and thin cross-sections. Moreover, it is noticed that the flutter frequency— for flutter loads obtained by coalescing either of the first and second or second and third flexural eigenfrequencies-never exceeds the precise value 11·01l… of Beck's column.