Variable temperature NMR spectroscopy is used to determine the ?H° and ?S° of hydrogen bond formation in a simple diamide. In this two- or three-day experiment, students synthesize N,N'-dimethylmalonamide, dimethylsuccinamide, dimethylglutaramide, or dimethyladipamide from methylamine and the corresponding diester (typically in 50% recrystallized yield) and record NMR spectra at temperatures between 200 and 313 K. Solutions of N-methylacetamide in concentrations between 1.00 mM and 13.1 M (neat) are prepared and their NMR spectra recorded to determine the chemical shift of the amide proton in the hydrogen-bonded (d[subscript B]) and nonbonded (d[subscript N]) limits. By using these data, the equilibrium constants, ?H°, and ?S° for the conversion of an open-chain diamide to a cyclic structure with an intramolecular hydrogen bond are determined.