During the past several years, there have been significant advances in NMR solution structure determination of macromolecules. The ability to easily measure residual dipolar couplings, to directly detect NHellipsisN hydrogen bonding interactions and to study much larger macromolecules by the application of heteronuclear experiments that select narrow lines in 2D and 3D spectra of isotopically labeled molecules promises to dramatically improve solution structure determination of nucleic acids.