Abstract: An aerodynamic device 24 for fitting to a vehicle 1 comprising a load compartment 10 having a roof 16 with front section 22, which is the section of the roof 16 towards an edge 20 of the roof 16 that is forward-most in relation to the direction of travel of the vehicle 1. The device 24 has an air guiding member 26 and an attachment structure 32 for attaching the member 26 to the vehicle 1 in a first, active position in spaced apart relation to the front section 22 of the roof 16 thereby to define an airway 34 between the member 26 and the front section 22 of the roof 16.