The past five years have seen a profound escalation in the need for large numbers of high quality synthetic peptides in the fields of molecular biology, immunology, pharmacology, biochemistry, biology, and chemistry. A major limiting factor in these studies has remained the availability, cost and purity of the desired peptides. Although it is currently possible, using available manual or automated methods, to produce large numbers of peptides (ie., hundreds), the effort is so time consuming and costly that to carry out this number of syntheses is normally impractical even in well equipped laboratories. Small laboratories and institutions are virtually precluded from carrying out research requiring large numbers of peptides. We have recently devised a procedure called simultaneous multiple peptide synthesis (SMPS), which permits the rapid simultaneous solid phase peptide synthesis of large numbers of peptides. In the proposed research SMPS will be optimized and in turn used to optimize synthesis protocols. Upon completion of the proposed research it is expected that laboratory personnel, even those without specific prior training in peptide chemistry, will be able to simultaneously synthesize at least 100 totally different peptide sequences having excellent purity, without the need for automated equipment, in a time frame (2-4 weeks) and cost at least 10 times less than currently available manual or automated methods.