Visionary landscape architect Lawrence Halprin’s The RSVP Cycles: Creative Processes in the Human Environment (1969) is an interdisciplinary model for collaborating through and with notation. In this article, I outline RSVP’s potential to articulate undertheorized connections between notation, collectivity, and improvisation in the work of a number of present-day composer-performers through the case study of British composer-improviser Richard Barrett’s fOKT series (2005). At the same time, I show this music can help redress a number of blind spots in Halprin’s own ideas about scores – especially the inclusive, participatory political vision that grounded them.