Crafted by the American physicist, philosopher of science and feminist theorist Karen Barad, most extensively in her book Meeting the Universe Halfway, the concept of intra-action has during the past decade come to exert a marked influence on contemporary theories and research. Not only is this concept central to Barad's own theory of agential realism, which strives to replace the assumed separateness of world and words, or the world's material processes and human discursive meanings, with their mutual dependence and co-constitution. The concept has also become a buzzword in several, and partly interwoven, wider strands of research across the humanities, arts and science studies. These strands range from posthumanist thinking and critical science and technology studies to new materialist thought in its feminist and other incarnations. But what does intra-action entail besides its idiosyncratic reconfiguring of the familiar word "interaction", and in addition to having become a staple term - some might argue a new piece of jargon - in certain theoretical debates and fields of research?

This special issue addresses this question at fresh intersections of new materialist thinking, artistic research, and art studies. For the emerging area of research initiatives labelled as new materialisms, intra-action has proved an attractive concept, because it helps to highlight the constitutive significance of technological, human bodily, and diverse non-human materialities in cultural, social and environmental realities without positing them as a self-contained sphere. Instead, intra-action allows one to explore how forms of materiality result from their differing interplays with discourses that signify them, and with historical and cultural practices that shape them. Crucially, this notion at the same time enables one to acknowledge that materialities themselves consist of active processes, which are capable of affecting, surprising and changing discourses and social practices in turn, always within specific webs of relation.