The major histocompatibility complex (MHC) presents canonical medium-high-affinity peptides on the surface of antigen-presenting cells to T-cells. Recognition of peptide MHC by T-cells initiates a cascade of signals which maintains a T-cell-dependent immune response. In the design of vaccines, there is need for an understanding of how peptides bind to MHC class I molecules. Herein, the presentation of canonical anchor motif peptides to MHC class I, noncanonical anchor motif peptides, low-affinity peptides, peptides making use of new pockets, short peptides, long peptides, glycopeptides, retro-inverso peptides and prediction programs for peptides binding to MHC class I molecules is discussed. All this information will aid in the design of new and improved peptide-based vaccines.