Every textile material, be it for low-end consumer goods or high-end technical products, is exploited for the properties resulting from its multi-scale nature (fibres -> yarns -> textiles -> derivatives). Understanding this multi-scale nature is thus key to improving this materials. Textiles are, for example, well suited for technical applications thanks to their unique combination of lightness, flexibility and strength. Yet such applications often require a thorough understanding of the mechanical performance, which in itself is quite challenging due to the complex microstructure. By following a multiscale analysis, combining both experimental and numerical techniques, starting with individual fibres and building up till complete textile materials and derivatives such as composites, we underpin the micro-macro relationships that govern the mechanical behaviour of textiles. This project combines both advanced testing methods with in-situ measurement of the deformation mechanisms at microscale, and novel finite element modelling tools that allow simulations at the microscale.