ABSTRACT The author discusses “score streams,” a compositional method in which notations are displayed dynamically on computer screens and interpreted by improvisers. These works are informed by contemporary explorations in telematic performance and by the many methods devised over the past half century in composer-improviser traditions, where works by individuals are understood as catalysts for profoundly collaborative real-time acts of creation. Referencing polyphony both literally and metaphorically, the author points to a richly generative dialogue between recent histories of improvised music and new forms of digital networking technologies.