The following chapter is intended as a warm-up reading exercise and as a first-level introduction to the study of sustainability. Before we can familiarise ourselves with the terminology associated with sustainability and then explore the chapters that follow, we need to understand what premise we are starting our investigative venture from. More importantly, we need to understand our own positionality in this study process. Sustainability is an incredibly complex and multifaceted subject of study, and it requires us to approach it with our eyes wide open. When you study sustainability and the world around you more generally, you need to read, interpret, and analyse everything not only with an open mind but also through a critical lens. The latter has always been important but is even more important with the current challenges that we face. The following chapter begins by unpacking the complexities of sustainability as a field of study. It then highlights the importance of understanding one’s own positionality and that of others when studying sustainability, before introducing concepts such as ontology and epistemology, which are foundational to our sustainability study. The discussion continues with an overview of systems thinking, reflection, and the notion of participation, all of which are important attributes in the field of sustainability study. Finally, the chapter concludes with a brief exploration of interdisciplinarity, its significance, challenges, and opportunities, offering an illustrative example on how interdisciplinarity can foster innovative teaching, learning, and practice in sustainability.