A unique method to generate large numbers of different peptides is the SPOT method for synthesis of peptide arrays on cellulose membranes. Peptides are synthesized by repeated deposition of activated amino acids as spots on a specially derivatized filter sheet. This entire process has now been fully automated and can be adapted to the MultiPep RS synthesizer. Up to 2400 positions on freely defined grids can be addressed on the four synthesis membranes. An upgrade kit with hardware and software is available. This procedure is subject to extensive licensing conditions.