Abstract: A transmission 10 includes a drive member 12 which is rotatable about a first axis of rotation 20 and a driven member 14 which is rotatable about a second axis of rotation 26 and which is spaced axially from the drive member 12. The transmission 10 further includes an intermediate member 34 which is positioned between the drive and driven members 12, 14 and which is rotatable about a third axis of rotation 36. A plurality of axially displaceable drive elements 38 is provided for transmitting drive between at least one of the drive member and the intermediate member and the intermediate member and the driven member. The eccentricity of the intermediate member 34 relative to the drive and driven members 12, 14 is adjustable thereby to permit adjustment of the transmission ratio.