This dissertation explores the question of how art and science work as categories to circumscribe bodies of knowledge. I am interested in how specific knowledge communities label and materially shape artistic and scientific objects in contexts. People engage in rhetorical positioning th rough the creation of texts, style choices, making and unmaking the meanings of objects. Objects can be made to fit into the knowledge networks of art, science, or combinations of both. For different practitioners and audiences, what counts as art or science and their association vary in interesting ways. The categories of art and science serve many purposes. They indicate the kind of attention people, objects, and ideas want to elicit from readers, viewers, and thinkers. They serve to demarcate resources, to delineate interests, and to separate social groups. This dissertation contains three core case studies: the story of the Blaschka's 19th century glass scientific models, the story of the 1990s tactical media movement, and the story of bioarts as practiced in a wet biological lab in Australia. These cases serve to show that art and science are not stable categories and demonstrate ways those categories are maintained. By unpacking the ways actors have used these categories, I complicate the division between the realms of art and science, be reflexive about thinking with regard to the categories we use to make sense of things and the value and power-orientation assigned to those categories, and show that science studies tools can be applied to artistic practice with fruitful results that iii offer new ways of thinking about people and objects that have often fallen outside the scope of science studies research. My analysis details the forms of knowledge produced by art and science in these contexts. iv