Innovations in material engineering have consistently helped to improve everyday objects and infrastructures. However, the trade-off between performance and sustainability reveals limitations in current manufacturing approaches , specifically in (a) material microstructures, (b) production processes and (c) environmental impact:  (a1) Engineering complexity: biological systems present high levels of complexity, hierarchical control and automation that are hard to replicate synthetically .  (a2) Many engineered materials may be highly optimized for specific properties (e.g. stiffness) but are often less versatile .  (b1) Conventional microfabrication has high infrastructure costs, illustrated by semiconductor foundries .  (b2) Manufacturing tools and microstructures: although current microfabrication technologies can produce complex multi-scale materials, they cannot yet produce microstructures in large materials, at scale , as nature can .  (c1) Raw materials scarcity and energy costs: dependency on rare earth elements and fossil-based materials .  (c2) Sustainability: optimizing properties in engineered composites often introduces trade-offs on disassembly and recyclability , while biological materials are biodegradable.  (c3) Significant environmental and health impacts of conventional industrial facilities . In contrast, the versatile and competitive properties of biological materials stem from their (a) refined microstructures, (b) unique manufacturing, and (c) ecological integration , all of which could help address these limitations if successfully replicated . These hierarchical materials have mechanical properties essential in various industries ; for example wood tensile strength stems from its self-organized composite microstructure . Understanding such materials to mimic them synthetically (Fig. ) implies to first characterize their properties, hierarchical structure and self-assembly mechanisms . Second, the material-producing organ must also be studied to understand its physiology and development . Biological materials' intricate micro-architectures (a1) have been optimized through evolution for high mechanical performance and versatility (a2) (Fig. ). Organs such as the spider silk gland regulate complex processes, notably the molecular assembly of fibers . These organ production units are themselves self-organized following a developmental program. Instead of designing such highly complex systems from scratch, one can recapitulate the conditions guiding organogenesis . Starting with precise initial conditions and cell sources, highly complex tissues can self-organize and produce materials autonomously . Organoids illustrate this principle and can grow hierarchical materials, such as hair follicle organoids . These tissues, made of heterogeneous cell types differentiated from stem cells, show physiologically relevant behaviors that can mimic material-producing organs . This approach could lead to living machines , potentially produced in large numbers by leveraging self-organization . Moreover, they can grow microstructured materials at macroscopic scales, as observed in nature (b2), using abundant raw materials . The final products can be highly complex while biodegradable . Organ production units can themselves be recycled, thus reducing the environmental impact .