A method of and apparatus for improving the efficiency of a data processing system employing multiple busses operating at multiple data transfer rates. Each of the multiple physical busses has its own characteristics including maximum data transfer rate, parallel word width, etc. Two or more of these physical busses are combined into a single logical bus, wherein the single logical bus has characteristics resulting from the combination of physical busses. These characteristics can include greater parallel word widths, enhanced maximum data transfer rates, etc.