A system for managing the transfer of agricultural material from a material-transferring vehicle to a material-receiving vehicle. An unloading chute is adapted to transfer material from a first storage container of the material-transferring vehicle to a material-receiving vehicle alongside the material-transferring vehicle. A location-determining receiver is adapted to estimate position data for guiding the material-transferring vehicle. An image sensor is mounted on the material-transferring vehicle or the first storage container for estimating a lateral separation distance between the first storage container and the material-receiving vehicle for receiving the material. An electronic data processing system guides the material-transferring vehicle based on the estimated position data and the estimated lateral separation distance, to maintain a generally constant target lateral separation distance between the material-transferring vehicle and the material-receiving vehicle during the transfer of the material.
