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A series of polycrystalline samples containing sillenite-like (doped γ-Bi₂O₃) phases were prepared by high-temperature reactions from α-Bi₂O₃ powder and different oxides in six pseudo-binary Bi₂O₃-M_xO_y (M = Mn, Ti, V) and six pseudo-ternary Bi₂O₃-M1_xO_y-M2_xO_y (M1 = Pb, Zn, Ti and M2 = Zn, Ti, Si) systems. The products were characterized by XRD, SEM/EDX, HRTEM, SAED and DTA techniques. It is shown that for pseudo-binary systems, the phase composition of specimens depends on dopant content, while, for pseudo-ternary systems, depends on dopants radii, as well. In pseudo-binary systems, single-phase sillenites are obtained if the dopant content is in accordance with formula Bi₁₂M⁴⁺O₂₀, for M = Mn and Ti, and Bi₁₂(M0.85+)O₂₀, for M = V. However, two coexisting sillenite-like phases, doped compound and nominally undoped solid solution, are found if a half of that dopant quantity is applied. In pseudo-ternary systems, the phase-pure double-doped sillenite specimens are identified if ionic radii of dopants differ less than 40%. Otherwise, two coexisting sillenites were obtained. The possibility to prepare the undoped γ-Bi₂O₃ phase was also discussed. © 2013 Elsevier Masson SAS. All rights reserved.