This mini-encyclopedia contains more than 1500 entries in alphabetical order from the entire field of peptide science, with illustrations and carefully selected bibliography for further study.

Areas covered in the encyclopedia include:

- biological peptides and small proteins
- peptide hormones
- pharmaceutical peptides
- peptide antibiotics
- peptide inhibitors
- peptide reagents
- peptide tags
- structural classes
- synthesis and purification
- analytical methods
- proteomics and peptidomics