An exhaust dilution and dispersion device for a vehicle, comprising: a generally elongate tailpipe comprising: (i) an inlet section, in use, capable of being in exhaust receiving communication with an exhaust system of the vehicle; and (ii) an outlet section in exhaust receiving communication with the inlet section, the outlet section comprising a downwardly directed exhaust deflection portion having side edges and an exhaust outlet in exhaust dispersing communication with the surroundings external to the device, the exhaust outlet comprising a generally elongate opening extending in a lengthwise direction of the tailpipe such that the opening is longer in the lengthwise direction than the opening is wide in a direction transverse to the lengthwise direction; wherein at least a portion of the exhaust outlet is coextensive with the downwardly directed exhaust deflection portion, and wherein a major portion of the exhaust dispersed from the exhaust outlet has a transverse component; the downwardly directed exhaust deflection portion comprising at least one exhaust flow deflector having a projecting portion projecting inwardly into the exhaust flow path of exhaust from the exhaust system when the exhaust dilution and dispersion device is mounted to the vehicle, the projecting portion being spaced from the side edges of the exhaust deflection portion to provide a path for exhaust to flow in the space between the projecting portion of the exhaust flow deflector and the side edges of the exhaust deflection portion, the exhaust flow deflector extending in the exhaust flow direction from an upper portion of the exhaust deflection portion toward a lower portion of the exhaust deflection portion, the projecting portion of the exhaust flow deflector having a lower portion with a greater width than the width of an upper portion of the projecting portion of the exhaust flow deflector, the projecting portion of the exhaust flow deflector impacting exhaust when the outlet section is in exhaust receiving communication with the inlet section and redirecting a portion of exhaust flowing between the exhaust flow deflector and side edges of the exhaust deflection portion away from the projecting portion of the exhaust flow deflector in a direction having a transverse component. a generally elongate tailpipe comprising: (i) an inlet section, in use, capable of being in exhaust receiving communication with an exhaust system of the vehicle; and (ii) an outlet section in exhaust receiving communication with the inlet section, the outlet section comprising a downwardly directed exhaust deflection portion having side edges and an exhaust outlet in exhaust dispersing communication with the surroundings external to the device, the exhaust outlet comprising a generally elongate opening extending in a lengthwise direction of the tailpipe such that the opening is longer in the lengthwise direction than the opening is wide in a direction transverse to the lengthwise direction; (i) an inlet section, in use, capable of being in exhaust receiving communication with an exhaust system of the vehicle; and (ii) an outlet section in exhaust receiving communication with the inlet section, the outlet section comprising a downwardly directed exhaust deflection portion having side edges and an exhaust outlet in exhaust dispersing communication with the surroundings external to the device, the exhaust outlet comprising a generally elongate opening extending in a lengthwise direction of the tailpipe such that the opening is longer in the lengthwise direction than the opening is wide in a direction transverse to the lengthwise direction; wherein at least a portion of the exhaust outlet is coextensive with the downwardly directed exhaust deflection portion, and wherein a major portion of the exhaust dispersed from the exhaust outlet has a transverse component; the downwardly directed exhaust deflection portion comprising at least one exhaust flow deflector having a projecting portion projecting inwardly into the exhaust flow path of exhaust from the exhaust system when the exhaust dilution and dispersion device is mounted to the vehicle, the projecting portion being spaced from the side edges of the exhaust deflection portion to provide a path for exhaust to flow in the space between the projecting portion of the exhaust flow deflector and the side edges of the exhaust deflection portion, the exhaust flow deflector extending in the exhaust flow direction from an upper portion of the exhaust deflection portion toward a lower portion of the exhaust deflection portion, the projecting portion of the exhaust flow deflector having a lower portion with a greater width than the width of an upper portion of the projecting portion of the exhaust flow deflector, the projecting portion of the exhaust flow deflector impacting exhaust when the outlet section is in exhaust receiving communication with the inlet section and redirecting a portion of exhaust flowing between the exhaust flow deflector and side edges of the exhaust deflection portion away from the projecting portion of the exhaust flow deflector in a direction having a transverse component.