This chapter explores the role of disciplinary thinking in STEM subjects (science, technology, and mathematics), emphasising the function as both a foundation for knowledge acquisition and a framework for interdisciplinary problem-solving. Disciplinary literacy and disciplinary thinking are intertwined, with the former equipping students with the necessary tools and language to engage deeply within a subject and the latter guiding inquiry, reasoning, and the construction of knowledge. While traditional classroom instruction often reinforces subject-specific expertise, contemporary educational challenges demand an integrative approach that balances disciplinary depth with interdisciplinary applications. The chapter explores the epistemological differences in the STEM subjects. A case study of the Australian Curriculum also analyses how disciplinary processes are conveyed through curriculum documents, shaping teaching and learning experiences. The chapter argues that an integrated STEM education must bridge disciplinary silos by fostering interdisciplinary approaches that maintain the epistemic integrity of each field while promoting holistic, systems-oriented learning. Educators can better prepare students for complex, real-world challenges by aligning disciplinary thinking with interdisciplinary imperatives. The chapter concludes with recommendations for integrating disciplinary knowledge into broader educational frameworks, advocating for a paradigm shift toward interconnected learning experiences that equip students with the skills necessary for a rapidly evolving global landscape.