The aim of this study is to explain from a fundamental perspective, how distributing the material thickness of a metal plate in different ways can be used to control the shape of the elastic buckling mode. The Evolutionary Structural Optimisation (ESO) method is modified to control the buckled shape of plates simply supported on three sides with the remaining longitudinal edge free. The bucking objectives are considered both from a fundamental perspective, and for the application of kinetic façade design, that is, façade panels that undergo shape changes to facilitate ventilation or shading control. A series of buckling experiments of optimised aluminium plates validates the optimised designs. It is shown that in order to achieve a maximum opening in a buckled plate, the buckled shape should be controlled in such a manner as to create a relatively flat zone of maximum transverse displacement over much of the displaced free edge, a shape that differs from the fundamental mode of a uniform thickness plate. Notably, such a shape may be achieved via optimisation with objectives that relate either to the shape itself, or to the objective of maximising the opening. The design methods and experiments demonstrate that redistribution of plate material can efficiently control the buckling characteristics of metal plates for desired functions, and provide significant performance enhancements over uniform thickness plates.