Interface to data stream synchronizing

A method of synchronizing first and second data streams, the first data stream acting as a reference stream, elements of the first data stream are displayed along a time line on a display device 22, 23. Containers for elements of the second data stream 12 are displayed on the display device alongside the elements of the first data stream. The containers are interactively displaced on the display device relative to the elements of the first data stream to align the containers with cue elements in the first data stream. Synchronization markers 38 are generated for the aligned displayable elements relative to the first data stream.