The compound [(CH3)C(NH2)(2)](4)[Re6Se8(CN)(6)] has been synthesized by the reaction at 200 degreesC for 3 days of Re4Te4(TeCl2)(4)Cl-8, KSeCN, and NH4Cl in superheated acetonitrile. This compound crystallizes in the space group C2/c of the monoclinic system with four formula units in a cell of dimensions a = 20.3113(14) Angstrom, b = 10.1332(7) Angstrom, C = 19.9981(14) Angstrom, beta = 106.754(1)degrees, V = 3941.3(5) Angstrom(3) (T = 153 K). The [Re6Se8(CN)(6)](4-) anion comprises an Re-6 octahedron face capped by mu(3)-Se atoms, with each Re atom liganded by a CN group. The anions and cations are connected by an extensive network of hydrogen bonds. The conversion of a Re(IV) tetrahedral cluster to a Re(III) octahedral cluster appears to be unprecedented.