The purpose of this dissertation is twofold. First, it explores how the notion of sustainability is conceptualized within early childhood education discourses and how it is manifested in early childhood curricula. Second, the dissertation examines post-anthropocentric possibilities of sustainability within early childhood education. A major finding of the two studies, relating to the first purpose, is that early childhood education tends to have an anthropocentric bias and over-emphasizes the importance of children’s agency in enhancing their potential to contribute to sustainability. Using this finding as a backdrop, the major finding of the two subsequent studies, relating to the second purpose, is that post-anthropocentric analysis can help to challenge these shortcomings and offer the emergence of a different sustainability ethos. In doing so, sustainability is reconceptualized as a generative concept that opens up possibilities for children to learn-with, become-with and be/become affected by non-humans, i.e. other species and non-human forces. Specific posthuman concepts such as assemblage, distributed agency and becoming-with are used as thinking tools. Systematic literature review and curricula content analysis are employed as methods for study one and study two respectively. Study three and study four draw ideas from post-qualitative inquiry which employ concepts that allow to experimentally engage with the world and think with/become-with data. The latter two studies empirically demonstrate emerging possibilities of learning for sustainability with the non-human others/material forces and other species. In the end, the dissertation highlights that post-humanist and new materialist perspectives can provide a post-anthropocentric conceptualisation of sustainability, which paves the way for a more relational ontology, one that could in turn create a pedagogical practice supporting sustainability. Parts of work Weldemariam, K. (2017). Challenging and expanding the notion of sustainability within early childhood education: Perspectives from post-humanism and/or new materialism. In O. Franck & C. Osbeck (Eds.), Ethical literacies and education for sustainable development: Young people, subjectivity and democratic participation (pp. 105-126): Palgrave Macmillanvisa artikel Weldemariam, K., Boyd, D., Hirst, N., Sageidet, B. M., Browder, J. K., Grogan, L.,HughesF.,(2017).Acriticalanalysisofconceptsassociatedwith sustainability in early childhood curriculum frameworks across five national contexts. International Journal of Early Childhood. 49(3), 333- 351visa artikel Weldemariam, K. (2020). Learning with Vital Materialities: Weather Assemblage Pedagogies in Early Childhood Education. Environmental Education Research journal- accepted for publication Weldemariam K. (2019). Becoming-with bees: generating affect and response-abilities with the dying bees in early childhood education, Discourse: Studies in the Cultural Politics of Education