Focusing on Michel Waisvisz’s No Backup (2004) and Hyper Instruments (ca. 1999), this chapter draws upon a range of examples relevant to a discussion around electroacoustic improvisation with new instruments and technologies. The approach to ‘analysis’ I shall take is in many ways a critique of some of the more traditional methods. The open-ended, interactive structures characteristic of digital media are not wholly compatible with conventional conceptualisations of music where ‘performers’ play ‘compositions’. Improvisation offers a distinctive mode of engagement, in that it not only challenges the separability of performance from composition, but also emphasises process over product, and is therefore more compatible with the interactive capabilities of new technologies. The impact of these issues on what we, as a culture, imagine musicians to be, and the interrogation of received notions of authorship and creativity, is an important undercurrent that shapes the discussion within this chapter.