▪ Abstract  During the past thirty years, deuterium labeling has been used to improve the resolution and sensitivity of protein NMR spectra used in a wide variety of applications. Most recently, the combination of triple resonance experiments and ²H, ¹³C, ¹⁵N labeled samples has been critical to the solution structure determination of several proteins with molecular weights on the order of 30 kDa. Here we review the developments in isotopic labeling strategies, NMR pulse sequences, and structure-determination protocols that have facilitated this advance and hold promise for future NMR-based structural studies of even larger systems. As well, we detail recent progress in the use of solution ²H NMR methods to probe the dynamics of protein sidechains.