[en] The ratios of cross peak intensities in a selective constant-time NOESY experiment, recorded with and without ³¹P decoupling, yield values for the sum of the H3'-P scalar and dipolar couplings. The selective refocusing of H3' resonances in this experiment results in excellent resolution and sensitivity, even in the liquid crystalline phase where the ¹H spectrum is broadened by unresolved homonuclear dipolar couplings. The vicinal H3'-P scalar and dipolar couplings in the DNA oligomer d(CGCGAATTCGCG)₂ were measured in both isotropic solution, and in a liquid crystalline phase. Isotropic values are in good agreement with values reported previously. Dipolar couplings are in excellent agreement with the NMR structure for this dodecamer, and to a somewhat lesser extent with the X-ray structures