This project aims to study the structure and dynamics of high latitude auroral arcs using data from the Sondrestrom incoherent scatter radar and an all-sky imaging photometer. The study will also make use of simultaneous and coincident low and mid-altitude in-situ satellite measurements of plasmas and fields to quantify electrodynamic parameters involved in magnetosphere-ionosphere coupling. The main objectives of this project are to study (1) the electrical structure near high latitude arcs with emphasis on the relative motion between the arc and the ambient plasma, (2) the relationship between radar, optical and satellite signatures of arcs, and (3) quiet time temporal and spatial variations of auroral structures. A future campaign is planned in which radar and optical measurements will be made in coordination with overpasses of the NASA FAST Small Explorer satellite.