Under the umbrella of biologically informed disciplines, biomimicry is a design methodology that proponents often assert will lead to a more sustainable future. In realizing that future, it becomes necessary to discern specifically what biomimicry’s “promises” are in relation to sustainable futures, and what is required in order for them to be fulfilled. This paper presents research examining the webpages of the Biomimicry Global Network (BGN) to extract the claims and promises expressed by biomimicry practitioners. These promises are assessed using current literature to determine their presuppositions and requirements. Biomimicry’s promises are expressed in terms of potential for innovation, sustainability, and transformation and appear to depend on perceived relationships between humanity and nature; nature and technology; the underlying value judgements of practitioners. The findings emphasize that in order for the communicated promise of biomimicry to be realized, a particular ethos and respectful engagement with nature must accompany the technological endeavors of the practice.