Mondrian Transcription Software is an open-source tool to transcribe fine-grained movement data from video by efficiently tracing the movement of people or things over floor plan representations to generate text files of positioning data — essentially, a transcript of movement. These files can be visualized in software such as the Interaction Geography Slicer. While there are increasingly many automated methods to interpret video or collect positioning data through location-based technologies, these methods continue to be imprecise and background the value of manual transcription practices that many qualitative researchers value. We are rapidly developing and expanding features of this tool and collaborators in this effort are welcome.