Suitable reactions of ABr, Zr, ZrBr4, and an interstitial Z element in Ta containers at 850 degrees C afford two series of quaternary cluster phases containing A(4)Br(3+) ions. Cubic (A(4)Br)(2)Zr-6(Z)Br-18 phases occur for various combinations of A = Na-Cs, Z = Be, B, H, Mn. The combination with A = K, Z = B was structurally characterized (inverse fluorite, Fm (3) over bar m, Z = 4, a = 16.191(2) Angstrom). The 15-e cluster exhibits the appropriate magnetic moment, and this decreases toward the diamagnetic 14-electron limit in products with potassium deficiencies, (K4-x)(2)Zr6Br18B, X less than or equal to similar to 0.5 The tetragonal Cs4Br[Zr-6(B)Br-12]Br-4 (P (4) over bar 2(1)m, Z = 2, a = 12.5482(7) Angstrom, c = 11.5610(9) Angstrom) contains a new type of puckered M6Br16 layers with Cs4Br3+ in tunnels normal to the layers. Both examples of A(4)Br(3+) ions have short central Br-A bonds plus three to nine more distant bromines in neighboring clusters about each A, respectively.