This study deals with the postbuckling and vibration behavior of flat and shallow curved panels resting on a Winkler linear/non-linear elastic foundation. The considered plate/shell structural model is based on a higher-order shear deformable theory and encompasses a number of effects such as transverse shear, geometric non-linearities and the initial geometric imperfection. Special emphasis is given to the influence played by Winkler's foundation moduli as well as by the previously mentioned effects upon the postbuckling and vibrational response in the pre/postbuckling ranges and a number of pertinent conclusions are outlined. (C) 1997 Elsevier Science Ltd.