INTRODUCTION: DOING THEORY"Theory is about whose lives matter and how." [Stefan Helmreich] DG&ZA: In this Matterphorical issue, we want to think about the production of meaning in its inextricability from matter, with meaning understood not as a simply semiotic or symbolic quality or quantity, but rather as something constantly being carried (phora/ϕορά) 'with', 'after' or 'between' (meta-/μετα-) semantic domains while also always traveling with or through an entanglement with matter -where "matter" is understood not as fixed substance, but, following Karen Barad's claim, as "substance in its intra-active becoming," as such "not situated in the world" but "worlding in its materiality." 1We are concerned with those political, aesthetic, legal, social, technological, physical, and environmental entanglements that not only shape but are onto-epistemologically constitutive of processes of knowledge and meaning production and transmission.We are interested, in other words, in theory -not only understood as a way of conceptualizing, but also as a mode of making sense of and sensing material-discursive practices. We assume neither a singular nor universal approach to theory, but rather seek modes that traverse disciplines, genres of analysis, and fields of knowledge. Doing theory, as we understand it, also means working collaboratively rather than under the assumption that ideas are the products of singular ingenious minds, products to be owned and defended by their authors, or to be articulated in intellectual and spatial isolation. We think, thus, not of "theory" in the abstract, but of doing theory.