Bulk In-doped ZnO crystals have been grown hydrothermally by adding In 2 O 3 to the normal nutrient. The major growth occurs along the [10−10] direction rather than the usual [0001] and [000−1] directions; thus, a c-plane crystal has a plate-like shape. Secondary-ion mass spectroscopy (SIMS) measurements reveal an In concentration of about 1.6×10 19 cm −3 in the bulk, with lesser amounts of Al (2.5×10 18 ), Ga (1.8×10 17 ), Fe (6.5×10 18 ), and Li (1.1×10 18 ). Low-temperature photoluminescence (PL) from the Zn face (0001) shows strong, relatively sharp donor-bound exciton (D°X) lines at 3.3609 and 3.3624eV, attributed to Al and H, respectively, along with much weaker lines at 3.29, 3.22eV, and 2.35eV, tentatively assigned, respectively, to a 1-LO-phonon replica of the D°X transitions, a donor–acceptor-pair transition, and the usual green band of unknown origin. The D°X-related PL from the O face (000−1) is much broader because of significantly higher In, Li, and Fe concentrations; however, it also includes a weak, sharp In°X line evidently emanating from the bulk region. The Hall-effect measurements in the range 15–320K reveal an unusual temperature variation of carrier concentration n, mobility μ, and resistivity ρ, namely the existence of two flat regions: (1) from 15 to 50K (n=7.8×10 18 cm −3 , μ=48cm 2 /Vs, and ρ=0.017Ωcm) and (2) from 250 to 320K (n=7.3×10 18 cm −3 , μ=83cm 2 /Vs, and ρ=0.010Ωcm). A mobility analysis based on degenerate electrons gives donor N D and acceptor N A concentrations of about 1.5×10 19 and 7.5×10 18 cm −3 , respectively. Remarkably, within error, N D ≈[In]+[Al]+[Ga] and N A ≈[Fe]+[Li].