In the early 20th century a Hungarian mathematician and philosopher, Valéria Dienes founded an art-of-movement school, the School of Orchestics. During my research on the connection between music and movement in this modern dance style I discovered seven handwritten notebooks and further pages full of unusual signs as well as notes which explained them. This study sets out to describe the meaning and use of these signs – a dance notation invented and used by Dienes and her pupils around 1916–1921 as an aid to creating a comprehensive theory of movement as well as for the purpose of recording the choreographies they created and performed on stage. Even though the existence of orcheography has been briefly mentioned in previous publications dealing with the history of the School of Orchestics, my paper is the first attempt at giving a detailed account of it. My work is based on primary source materials which were preserved in the estate of Dienes as well as that of her student and colleague, Mária Mirkovszky.