Biological systems use structured, hierarchical and nano-scaled building blocks to develop multiple functions. They are best exemplified by rod-like, chiral particles such as cellulose and chitin nanocrystals, which display thermo-mechanical and optical properties that are central to the field of biomimicry. Together with nanolignins and other materials produced from renewable resources, such particles are being explored as possible solutions to the future material demands. The interfacial assembly and structuring in water, the natural biosynthesis medium, dictate the opportunity for any potential utilization. This talk summarizes our experience in this area, considering fundamental aspects such as the interactions and the self- and directed assembly at solid/liquid, liquid/liquid and gas/liquid interfaces. Recognizing the importance of these aspects, several examples of advanced materials produced from cellulose, lignin and chitin will be introduced, including those with bioactivity, stimuli-responsiveness and capabilities for energy harvesting.