The oxovanadium(IV)-binding features of various oligopeptides are reviewed in the paper. The decisive role of amide coordination and the presence of a suitable anchoring donor group in the molecules are discussed through numerous examples. It is found that the effectiveness of the anchoring donors in promoting peptide amide deprotonation and coordination follows the sequence: phenolate-O - >alcoholate-O - , thiolate-S - >carboxylate-COO - >NH 2 . This basic sequence is finely tuned by the presence of additional donors in the molecule, and also by the presence of additional binder molecules in the biological fluids.