Infrared absorption bands attributable to the localized vibrational modes for several Al-related point defects have been observed for CdTe. The proposed defects, their point-group symmetries, and the vibrational frequencies at 80 °K in cm−1 are as follows: AlCd, Td, 299; AlCd-VCd, Cs, 282,287,326; AlCd-SbTe, C3v, 279,334; AlCd-CuCd, Cs, 291,294, 310; AlCd-AgTe or AlCd-Agi, C3v, 293,314; AlCd-AuTe or AlCd-Aui, C3v, 292,313; and possibly AlCd-AuCd, Cs, 288 (two unresolved bands), 326. The Al and Sb were introduced during crystal gwoth and the Cu, Ag, and Au by saturation diffusions. Annealing of CdTe:Al with [Al]∼1×1019 cm−3 in unsaturated Cd-rich atmospheres produced electron concentrations of 2×1018 and 2×1017 cm−3. Free-carrier absorption measurements at 298 and 80 °K give a nearly temperature-independent absorption coefficient with a frequency dependence of ω−3 after ther higher carrier density anneal with ω−4 for the lower carrier concentration. The free-carrier absorption results are compared with previously reported data and also recent theoretical calculations for CdTe which predict, under appropriate conditions, α∼ω−3 for the polar optical mode scattering and α∼ω−4 for ionized impurity scattering.