Activity Diagrams' are diagrams used by architects to examine activities occurring inside a given program with the aim of reorganizing the space and structure around these activities. Utilized earlier by Le Corbusier and the Situationists, these diagrams have taken on a new and complex form within dynamically evolving activities. The work of nine architectural practices are examined in this light and accompanied by extensive illustrations and documentation including: Actar Arquitectura, IaN+, Njiric+Njiric, UN Studio and Vincent Guallart.