Owing to extensive potential applications in various engineering areas, the mechanical metamaterials with unique and remarkable mechanical properties, such as shape-morphing, tunable Poisson’s ratio, tunable stiffness and multi-stability, have gained increasing interest from both academia and industry recently. Although those functionalities of existing mechanical metamaterials can be possessed by engineering their microstructures precisely, they are hard to adjust once fabricated. Elastic instabilities surround us every day: skin wrinkles and umbrellas snap inside out. Conventional engineering design principles commonly aim to prevent these instabilities, but over the past few decades, a positive side has emerged in which elastic instabilities give rise to new means to fabricate complex and responsive structures in a range of applications. A striking use of elastic instabilities is to design mechanical metamaterials [1,2,3], which are exploited in applications from energy storage and biomedical devices to soft robotics. Built upon the expertise of supervisor(s) on elastic instabilities and structural mechanics, this project aims to develop a general strategy in which elastic instabilities (such as Euler buckling and Snap-through) are used to generate metamaterials with programmable mechanical behaviours, whilst retaining the flexibility to reprogramme the given material to attain a different state later.