This paper addresses some of the practical issues associated with solution NMR investigations of high-molecular-weight ( > 20 kDa) biomolecules and their complexes. The experimental example of a high-molecular-weight system used here is a 52 kDa Fab/peptide complex. Theoretical as well as experimental aspects of solution NMR techniques employed to study such larger systems are discussed. Specific topics covered include hardware considerations, solvent suppression, and the relative efficiencies of various isotope-edited NMR techniques. Typical NOE methods used to derive structural information on these higher-molecular-weight systems and the scope of structural detail achievable are also examined.