This academic chapter from Harris's 2024 work, "Post-structuralism and Post-Modernism," introduces the core concepts of these intellectual movements that emerged in the late 1960s, challenging established Enlightenment thinking and structuralism. It outlines key figures like Foucault, Derrida, Lyotard, and Baudrillard, explaining concepts such as discourse, deconstruction, hyperreality, and biopolitics, and their impact on social theory, including the rejection of binaries and new understandings of subjectivity. The text also discusses criticisms of these approaches, such as relativism and obscurantism, referencing academic hoaxes and debates, before concluding with their lasting influence on social research through methods like Critical Discourse Analysis. Finally, it points to further reading, encompassing both primary texts from key theorists and secondary analyses of their ideas.