The visibility of queerness in mainstream culture is increasing, including a wider representation of gender expressions and sexual orientations – meaning that they are now named (such as transgender and non-binary). Questioning existing categories of gender and sexuality also finds its expression in literary works. This research project scrutinizes the literary experiments of Kathy Acker and aims to reveal how Acker problematizes existing categorizations of gender and sexuality, parallel to innovations in queer theory of the 1990s which have become part of the discourse on sexuality today. Acker's oeuvre is considered to be one of the most significant collections of experimental writing in English. Scholarly enquiries into Acker's works consist mostly of interpreting her experiments as postmodernist – due to her collage-techniques – and as feminist – viewing her fragmented texts as expressing a "female voice". What both of these approaches overlook is the way in which the instability of identity is connected to sexuality. My research project aims to fill this gap by studying Acker with queer theory, hypothesizing that Acker's experimental texts explore the constructed nature of identity through their emphasis on performativity of gender and rejection of binary conceptions of sexual orientation. I propose that sexuality in Acker's work is characterized by the affirmation of non-identity: a sexuality that is not based on sexual identity but rather on the fluidity of desire.