Abstract: Editing large-scale crowd animation is a daunting task due to the lack of an efficient manipulation method. This paper presents a novel cage-based editing method for large-scale crowd animation. The cage encloses animated characters and supports convenient space/time manipulation methods that were unachievable with previous approaches. The proposed method is based on a combination of cage-based deformation and as-rigid-as-possible deformation with a set of constraints integrated into the system to produce desired results. Our system allows animators to edit existing crowd animations intuitively with real-time performance while maintaining complex interactions between individual characters. Our examples demonstrate how our cage-based user interfaces mitigate the time and effort for the user to manipulate large crowd animation.