The preparation and structural characterization of three complexes containing the [Re2X8]2- (X=Cl or Br) anion are described. Crystallographic parameters are as follows: for [HPnPr3]2Re2Cl8 (1) a=33.831(9), b=11.274(6), c=18.286(5) Å, β=91.11(1)°, V=6955(7) Å3, Z=8, space group C2/c; for [PMePh3]2Re2Cl8 (2) a=10.861(2), b=11.964(3), c=16.235(4) Å, β=93.40(2)°, V=2106(1), Z=2, space group P21/n; for [PMePh3]2Re2Br8 (3) a=10.964(2), b=12.198(2), c=16.421(2) Å, β=93.83(1)°, V=2191(1) Å3, Z=2, space group P21/n. These complexes exhibit an unusual form of crystallographic disorder which has been previously observed in other derivatives that contain the [Re2X8]2- anion. It is suggested that while this type of disorder must correlate with the positions of the cations relative to the anions in the crystal packing, and other factors, no simple analysis is likely to be adequate. © 1990.