A document processing apparatus comprises a document transport path which extends from an upstream end to a downstream end, a low speed drive disposed at the upstream end of the document transport path and for transporting a document along the document transport path from the upstream end towards the downstream end, a high speed drive disposed at the downstream end of the document transport path and for receiving a document being transported along the document transport path from the low speed drive, an actuatable document processing device disposed at the downstream end of the document transport path and for, when actuated, performing a downstream processing operation on a document being transported along the document transport path, a sensor for (i) sensing speed of movement of a document which is being transported along the document transport path from the upstream end to the downstream end, and (ii) providing a first electrical signal which is indicative of speed of movement of the document, and a controller for (i) monitoring the first electrical signal to thereby monitor speed of movement of the document along the document transport path, (ii) detecting when speed of movement of the document has increased from a first speed to a second speed which is greater than the first speed, (iii) providing a second electrical signal to actuate the document processing device to perform the downstream processing operation in response to detection of speed of movement of the document having increased from the first speed to the second speed.