Sandwich panels exhibit various types of buckling modes depending on the steel face used. For the flat and lightly profiled sandwich panels, flexural wrinkling is an extremely important design criterion. A well established analytical solution exists for the design of flat faced sandwich panels, however, the analytical solution for the design of lightly profiled sandwich panels is based on simple modifications of the methods utilized for flat faces to take into account the flexural stiffness of the lightly profiled faces. In lightly profiled panels, as the depth or spacing of the ribs increases, flat plate buckling between the ribs can occur leading to the failure of the entire panel due to the interaction between local buckling and wrinkling modes. This interactive buckling behaviour should be taken into account in the design of lightly profiled sandwich panels. Therefore a research project was undertaken to investigate the interactive buckling behaviour of lightly profiled panels with varying depths and spacings of the ribs using an extensive series of experiment and finite element analysis. This paper presents the details of this investigation and the results.