Abstract: The invention provides a method and apparatus for pipelining the transformation of information between heterogeneous sets of data sources. The invention avoids intermediate data staging by constructing metadata that allow the acquisition of data in an order that matches the order in which the target data must be delivered. In a further feature of the invention, the acquisition, transformation, and delivery stages of an interface between two applications are pipelined as three processes that execute simultaneously on a continuous flow of data. Pipelining is a well-known technology that has been in use in operating systems, such as UNIX pipes and more recently by Torrent systems, to optimize the usage of multiprocessor machines. Uniquely, the invention applies pipelining technology to data transformation between heterogeneous data sources.