A mower-conditioner (2, 6) for cutting and conditioning crop material, comprises a mower unit (2) for cutting crop material and a conditioner unit (6) that is configured to condition the cut crop material. A drive input (10) is configured to receive a rotational drive from an external drive unit, and a drive transmission system (30) is configured to transmit rotary drive from the drive input (10) to the mower unit (2) and the conditioner unit (6). The drive transmission system (30) includes a continuously variable transmission (CVT) (40) that transmits rotary drive between the mower unit (2) and the conditioner unit (6) with a variable speed ratio.
