In this paper are reviewed a number of recently obtained (Me 6 L 1 8 n - based halides and oxyhalides with rare earths as countercations: M x REMe 6 X 1 8 (KLuNb 6 Cl 1 8 type, R3, and CsLuNb 6 Cl 1 8 type, P31c) and REMe 6 X 1 3 O 3 (ScNb 6 Cl 1 3 O 3 type, 14,22). Their crystal structure data, obtained from isotypic compounds with judiciously chosen M-RE-Me-X combinations, have allowed us to discuss rigorously the most important structural features appearing commonly in the Me 6 cluster chemistry: the systematic evolution of the Me-Me intracluster and the Me-ligand distances, depending on both electronic and steric effects. The influence of countercation size on the (Me 6 L 1 8 n - stacking is also considered. All these results form the basis of a consistent understanding of the (Me 6 L 1 8 n - based chemistry, when substitutions are performed on the various elements constituting these compounds.