A method and apparatus for transmitting a plurality of data streams in a wireless broadcast system are provided. The method includes mapping the plurality of data streams onto a super-frame that includes a plurality of frames; inserting signalling information in a first signalling information field for assisting in the reception of a first number of said plurality of data streams for a given frame, the first number being less than or equal to a limit applicable to each of the plurality of frames; dependent on a number of data streams for the given frame being greater than the limit, inserting signalling information in a second signalling information field; inserting said first and second signalling information fields in a preamble section of said given frame; and transmitting the plurality of frames.