You would have to give more details about what your trying to do before I could give you more specific help. Show an example of the records in each input file (relevant fields only) and what you expect for output. Explain the "rules" for getting from input to output. Give the starting position, length and format of each relevant field. Give the RECFM and LRECL of the input files. If file1 can have duplicates within it, show that in your example. If file2 can have duplicates within it, show that in your example.