The natural vibration and flutter characteristics of two corrugation-stiffened panels were studied experimentally and theoretically to determine the effects of finite deflectional, rotational, and torsional stiffnesses of the boundary supports. Flutter tests were conducted at a Mach number of 3. The experimental data are compared with results from a flutter theory for orthotropic panels which includes the effects of finite support stiffnesses as well as uniform in-plane loading of the panel. The investigation indicates that finite deflectional, rotational, and torsional stiffnesses of the boundary supports must be accounted for in the theory in order to match experimental natural frequencies of the test panels. However, it is concluded that structural damping (neglected in the theory) strongly influenced the flutter behavior of the test panels. Furthermore, the theory shows that the addition of torsional stiffening at the supports is a definite asset for increasing flutter dynamic pressure and may be extremely important in the design of panels for application at hypersonic speeds where thermal expansion may be desired.