NMR studies of protein-ligand interactions range from using NMR as a t
ool with which to monitor ligand binding to the determination of the t
hree-dimensional structure of complexes at atomic resolution. In recen
t years, selective and uniform enrichment with stable isotopes has pro
moted the investigation of ever larger systems at increasing resolutio
n, and significant advances have been made using NMR techniques that f
ocus specifically on the interaction of proteins and ligands.