This chapter explores the philosophical and biological concepts of poiesis and closure, focusing on Donna Haraway’s critique of autopoiesis and her advocacy for sympoiesis as a more comprehensive framework for understanding living systems. Haraway’s work challenges the reductionist and mechanistic paradigms of traditional evolutionary theory, emphasizing instead the symbiotic and relational nature of organisms. Drawing on endosymbiotic theory and organicism, the chapter argues that biological systems are best understood as dynamic, multispecies consortia (holobionts) rather than isolated individuals. The discussion contrasts autopoiesis, which prioritises internal self-maintenance, with sympoiesis, which highlights the constitutive role of interspecies interactions in development and evolution. The organisational approach, particularly the notion of closure of constraints, is presented as a way to reconcile these perspectives, offering a dialectical model where organisms and environments co-constitute each other. Ultimately, the chapter advocates for a processual and ecological view of life, underscoring the limitations of systems theory and the need for a more integrative, diachronic biology.