The invention concerns a cutting and/or carrying unit for a harvester, the cutting and/or carrying unit having: a series of cutting and/or carrying segments, each segment in the series being adapted to cause cutting of a crop and/or carrying of the crop; a cutting and/or carrying unit circuit around which the series of segments travel; and a driving mechanism to drive movement of the series of segments around the circuit; wherein the driving mechanism drives movement of the series of cutting and/or carrying segments around the circuit to cut the crop and/or to carry harvested crop, as the series of segments travels around the circuit. The invention also concerns harvesters incorporating said cutting and/or carrying units.