Parallel data generated by demultiplexing received serial data such as in a Serial RapidIO (SRIO) data stream can become misaligned as a result of, e.g., clock tolerance compensation (CTC) processing at the receiver. In one embodiment of the invention, the misaligned parallel data is properly aligned based on a mapping from each of a finite number of possible previous alignment conditions (e.g., words A-D) to a corresponding finite number of possible subsequent alignment conditions (e.g., words B-G). The change from a previous alignment condition to a different subsequent alignment condition is recognized by determining the location of start-of-packet (SOP) or start-of-control-symbol (SOC) data in the parallel data stream.