Reactions of nine-atom deltahedral clusters (Zintl ions) of tin, Sn-9(4-), with alkyl chlorides, RCl (R = Bu-t, Bu-n, Bu-s), and alkynes (Me3Si-C C-SiMe3, Ph-C CH) yielded the corresponding alkylated and alkenylated clusters [Sn-9-R](3-). The triple bonds of the alkynes are hydrogenated to double bonds in the process. These are the first tin-based organo-Zintl ions, that is Zintl ions of tin that were subsequently functionalized with organic groups. They are analogous to the recently reported germanium-based derivatives. The Bu-t-, vinyl-, and styrene-functionalized clusters [Sn-9-Bu-t](3-), [Sn-9-CH=CH2](3-), and [Sn-9-CH=CH-Ph](3-), respectively, were structurally characterized in the solid state with [K(2,2,2-crypt)](+) countercations and in solution by electrospray mass spectrometry. Crystal data: [K(2,2,2-crypt)](3)[Sn-9-Bu-t] center dot 2py, triclinic, P1, a = 14.4259(3), b = 16.2725(4), and c = 22.5593(5) angstrom, alpha = 86.092(1), beta = 78.952(1), and gamma = 65.114(1)degrees, V = 4714.48(7) angstrom(3), Z = 2; [K(2,2,2-crypt)](3)[Sn-9-CH=CH2]center dot 2py, triclinic, P-1, a = 15.6988(3), b = 17.4195(4), and c = 17.4432(4) angstrom, alpha = 86.299(1), beta = 81.566(1), and gamma = 85.349(1)degrees, V = 4696.27(18) angstrom(3), Z = 2; [K(2,2,2-crypt)](3)[Sn-9-CH=CH-Ph] center dot tol center dot 0.75py, monoclinic, C2/c, a = 38.5883(9), b = 23.3893(5), and c = 25.0192(5) angstrom, beta = 120.269(1) degrees, V = 19502.6(7) angstrom(3), Z = 8.