This study introduces the original rubric of ‘speculative flesh ecologies’ by bringing together the concept of ‘flesh’, the ethical approach of ‘indistinction’, and a strand of twenty-first-century speculative fiction interested in human and nonhuman ontologies and ethical relationships. It challenges human/nonhuman distinctions, and explores the wide range of multi-species possibilities imagined by the ‘speculative flesh ecologies’ of contemporary speculative fiction. Through five kinds of flesh in speculative fiction – human, animal, plant, thing and cultured – this book demonstrates the value of ‘speculative flesh ecologies’ as an approach for understanding and embracing the seemingly disparate ontologies of humans and nonhumans, making present new forms of ethical thinking that explore what it means to live as, with and through other fleshy beings.