Measurements of both electrical conductivity and thermoelectric power were used to monitor the equilibration kinetics of undoped single-crystal TiO2 during prolonged oxidation at 1123 and 1323 K and p(O-2) = 75 kPa. Two kinetics regimes were revealed: kinetics regime I (rapid kinetics), which is rate-controlled by the transport of oxygen vacancies, and kinetics regime II (slow kinetics), which is rate-controlled by the transport of titanium vacancies. The incorporation of titanium vacancies allows undoped p-type TiO2 to be processed in a controlled manner. The kinetics data were used to determine the chemical diffusion coefficient (D-chem) associated with the transport of titanium vacancies, which is equal to D-chem = 8.9 x 10(-14) m(2) s(-1) and D-chem = 9.3 x 10(-15) m(2) s(-1) at 1323 and 1123 K, respectively.