In this study, the elastic constants of a titanium diboride (TiB2) single crystal were measured using resonant ultrasound spectroscopy. In contrast to previous work, the current results are consistent with the measured elastic constants ofTiB2polycrystals. In addition, the crystal anisotropy ofTiB2was examined. The current data show that the elastic properties ofTiB2are much more isotropic than previously considered. ©1997 American Institute of Physics.