This open access book, in an era defined by an interplay of environmental, societal, and economic challenges collectively termed the “polycrisis”, the growing role of Early Childhood Education and Care (ECEC) emerges as a pivotal yet underappreciated element. Inspired by recent scholarship on crisis and sustainable futures, this volume advocates for a nuanced understanding of the polycrisis as not merely a cluster of crises to be resolved but as a multifaceted opportunity for profound introspection and a transformative reorientation of thought and action. The authors posit a reimagined role for ECEC in the landscape of sustainable development, underscoring the rich insights offered by children and the transformative power embedded within early educational methodologies. Throughout its five sections, this book proposes a new perspective, viewing the polycrisis not just as problems to be solved, but as opportunities for deep reflection and a shift in our ways of thinking and acting. It redefines ECEC's role in sustainable development by recognizing the unique insights of children and the transformative power of early childhood education. The volume goes beyond the traditional approach to global challenges, highlighting the lack of focus on children's viewpoints in addressing long-term sustainability. It brings forward innovative concepts from diverse fields such as Artificial Intelligence Contributions, Collaborative Contributions Intergenerational Contributions, Environmental Contributions, and Indigenous Contributions  Integrating collaborative, environmental, intergenerational, and indigenous insights interspersed with insights from emerging technologies in early childhood education and care fosters transformative wisdom. These intersecting bodies of knowledge  create inclusive, holistic pedagogical practices that contribute towards creating sustainable futures for all generations. Ultimately, the book aims to reveal principles and ideas that will transform ECEC practices, focusing on the well-being of both children and the environment. It seeks to integrate wisdom as an essential element in achieving sustainability, by embracing the dialectics of the polycrisis as catalysts for deeper understanding as well as innovative action.