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The static dielectric tensor is highly anisotropic in the tetragonal phase of barium titanate: the static dielectric constant perpendicular to the c axis, ɛ⊥, is 40 times that parallel to the c axis, ɛ∥, at T= 20 C, with this ratio decreasing to∼ 20 times at T= 90 C. Using both holographic and bulk measurements we show that the hole drift mobility has comparable anisotropy: the hole mobility perpendicular to the c axis, μ⊥, is 20 times larger than that parallel to the c axis, μ∥, at T= 20 C, with this ratio decreasing to 8 times at T= 90 C. We also show that μ∥/μ⊥∼ 2 ɛ∥/ɛ⊥ independent of temperature between T= 20 C and T= 90 C, suggesting that the hole drift mobility in barium titanate crystals scales with the static dielectric constant in this temperature range.© 1996 The American Physical Society.