In this work, we used the molten chalcogenide flux synthetic method to form an analogous series of alkali samarium selenogermanates, with the general formula ASmGeSe(4) (A = K, Rb, Cs). Using a constant reactant stoichiometry, we relate the monoclinic KLaGeSe4 structure type to the orthorhombic CsSmGeS4 structure type. KSmGeSe4 [in space group P2(1) with cell parameters a = 6.774(1) Angstrom, b = 6.994(1) Angstrom, c = 8.960(2) Angstrom, beta = 108.225(3)degrees, and V = 403.2(1) Angstrom(3) (Z = 2)], RbSmGeSe4 [in space group P2(1)2(1)2(1) with cell parameters a = 6.7347(8) Angstrom, b = 7.0185(9) Angstrom, c = 17.723(2) Angstrom, and V = 837.7(2) Angstrom(3) (Z = 4)], and CsSmGeSe4 [in space group P2(1)2(1)2(1) with cell parameters a = 6.707(2) Angstrom, b = 7.067(2) Angstrom, c = 18.334(6) Angstrom, and V = 869.1(5) Angstrom(3) (Z = 4)] were formed under identical synthetic conditions by changing the identity of the alkali ion from K to Rb or Cs, respectively. Additionally, with the substitution of sodium into the reaction, a triclinic structure with the approximate formula NaSmGeSe4 was found with the cell parameters a = 6.897(2) Angstrom, b = 9.919(2) Angstrom, c = 11.183(2) Angstrom, alpha = 84.067(4)degrees, beta = 88.105(4)degrees, gamma = 73.999(4)degrees, and V = 731.5(3) Angstrom(3). In addition to single-crystal diffraction, Raman and diffuse reflectance UV-visible spectroscopic measurements have been used to characterize these compounds.