Colour-changing and light-emitting textile structures can be developed using chromic or luminescent materials. They are able to change their optical properties when a specific stimulus is applied to them. This stimulus can be optical, thermal, electrical, chemical or mechanical. Luminescent materials are able to emit light; electroluminescent diodes are a well-known example. Chromic materials are able to change their colour without any light emission. Some of these textile-based structures have already been used for the development of flexible displays, which can be used for multiple applications, from medical textiles to communicative textiles, as well as for art and fashion.