In an effort to produce new and more sustainable technologies, designers have turned to nature in search of inspiration and innovation. Biomimetic design (from the Greek bios, life, mimesis, imitation) is the conscious imitation of biological models to solve today's technical and ecological challenges. Nowadays numerous different approaches exist that take inspiration from nature as a model for design, such as biomimicry, biomimetics, bionics, permaculture, ecological engineering, etc. This variety of practices comes in turn with a wide range of different (...) promises, including sustainability, increased resilience, multi-functionality, and a lower degree of risk. How are we to make sense of this heterogeneous amalgam of existing practices and technologies, and of the numerous promises attached to them? We suggest that a typology of biomimetic approaches would provide a useful hermeneutic framework to understand the different tensions that pull this variegated landscape in different directions. This is achieved through a critical analysis of the literature in different fields of biomimetic design and the philosophy of biomimicry, in order to derive conceptual and normative assumptions concerning the meaning and value of the imitation of nature. These two dimensions are then intersected to derive an analytical grid composed of six different biomimetic types, which enable the classification of existing and possible biomimetic approaches, practices, and technologies according to their specific conceptual assumptions and guiding norms. (shrink)