In this chapter, I turn to the media studies concept of “ambience”—an environmental disruption of figure-ground, text-context binaries—in the poetry of Tan Lin to locate emergent poetics at the center of a theory of textuality for the twenty-first century. Ambience has been part of Tan Lin’s poetic project for nearly two decades, despite (or perhaps because of) its definitional slipperiness and fundamental ambiguity. For Lin, a poet often associated with conceptual writing due to the appropriative nature of his poetry, ambience—a kind of immersive textual environmentalism—describes both the inputs and the outputs of his poetic process, blurring boundaries between text and context, author and reader. In particular, this chapter explores the implications of ambience in theories of the network and in media ecology, taking as a case study Lin’s work, commonly known as Heath but appearing in various forms as Heath: Plagiarism/Outsource, Heath Course Pak, and Tan Lin // plagiarism/outsource //, Notes Towards the Definition of Culture //,Untilted Heath Ledger Project //, a history of the search engine //,disco OS. Synthesizing contemporaneous conceptualizations of ambience from the fields of rhetoric, poetics, network theory and media studies raises the question of what role media ecology plays in a text such as Lin’s Heath, the ostensible contents of which are assembled from a variety of sources mediated by the internet. Finally, I argue (following Danny Snelson’s analysis of the implications of Actor-Network theory in Lin’s text) that Heath allows us to conceive of a non-anthropocentric theory of media in which texts, authors, and environments participate in a kind of pluralistic agency. This reading traces the multiplicity of agencies as play in Lin’s work, and the ambient networks into which they dissolve.