[en] Radiation defect creation processes in CsI(Tl) crystals have been studied. The model of color center, according to which Tl⁰ is close to anionic vacancy, is considered. The absorption spectrum of Tl⁰V_a⁺-center is a superposition of bands responsible for both transitions between the near activator exciton states and for those between the valent electron states in thallium atom perturbed by the anionic vacancy. Another center Tl⁺V_a⁺ may appear as a result of the Tl⁰V_a⁺ photoionization. Absorption bands at 3.44, 3.8, 2.64 eV of the electron trapping Tl⁺V_a⁺ in the center have exciton origin. Tl⁺V_a⁺ is also a luminescence center. The excitation in the absorption bands of this center luminescence is conditioned by the luminescence of the near activator excitons