Abstract: A method and apparatus for selecting a data stream in an access to a shared bus in a computer system. The method begins by requesting access to the shared bus. An evaluation of whether a first or a second data stream is a higher priority data stream is performed after the access request. The higher priority stream is selected to access the shared bus. A bus agent implementing this method includes a data stream selector coupled to receive a plurality of data streams. Bus cycle generation circuitry is coupled to a bus request line and a bus grant line. A priority evaluation circuit coupled to the data stream selector and the bus cycle generation circuitry is configured to control selection of one of the plurality of data streams based on a priority selection.