The special edition presents readers with the latest research results in the field of modern composite materials. In articles of Chapter 1: Sustainable Bio-Based Composites explore techniques of the development and application of composites derived by reinforcing the base materials with natural fibres from renewable bioresources. The importance of reducing the impact on the environment while simultaneously preserving the strength characteristics of the resulting material, as well as ensuring the structural integrity and operational characteristics of structures made from it, is highlighted.