A decoder for use in an interactive television system in which items of enhanced content can be presented to users, the decoder comprising: a receiver for receiving enhanced content data, a signal comprising timing indications and a video stream; a memory for storing enhanced content data received by the receiver and a timing schedule indicating timings associated with the enhanced content data; a timer; playout means for presenting the video data to a user, and being responsive to the timer for presenting the enhanced content data stored in the memory to a user in accordance with the state of the timer and the timing schedule; and synchronising means for synchronising the timer in accordance with the received timing indications.
