Changes in the NMR chemical shift of backbone amide nuclei (1H and 15N) have been used to map the matrix metalloproteinase (MMP) binding site on the N-terminal domain of the tissue inhibitor of metalloproteinase-2 (N-TIMP-2). Amide chemical shift changes were measured on formation of a stable complex with the catalytic domain of stromelysin-1 (N-MMP-3). Residues with significantly shifted amide signals mapped specifically to a broad site covering one face of the molecule. This site (the MMP binding site) consists primarily of residues 1-11, 27-41, 68-73, 87-90, and 97-104. The site overlaps with the OB-fold binding site seen in other proteins that share the same five-stranded beta-barrel topology. Sequence conservation data and recent site-directed mutagenesis studies are discussed in relation to the MMP binding site identified in this work.