Halogen nuclear quadrupole resonance data are presented for a number of compounds containing tetrahedral ZnX42- ions, where X = Cl, Br, and I. Characteristic mean frequencies are: for 35Cl in ZnCl42- 8.9 MHz ; for 81Br in ZnBr42- 60 MHz; and for 127I in ZnI42- 75 and 150 MHz. The number and relative intensities of the resonances for any compound is found to be a useful indication of the site symmetry of the ZnX42- ion, and compounds of unknown structure are examined in this light. 35Cl data are also presented for Cs2CuCl4, which has a mean frequency of 10.6 MHz at 298°K.