This manuscript provides a summary of the relatively large body of research on the preparation and characterization of dendrimers containing (1) multiple copies of metallocene residues on their surfaces or (2) a single metallocene residue at their core. Special emphasis is placed on dendrimers functionalized with either ferrocene or cobaltocenium groups, because their reversible electrochemistry makes them particularly attractive to the author's group. Dendrimers containing multiple, peripheral metallocene residues are of interest to develop multivalent interactions with suitable receptors or receptor assemblies. With dendrimers containing a single metallocene at their cores, the key questions relate to the effects of the dendritic mass on their properties and degree of encapsulation or site isolation. We focused our work on the electrochemical properties of these dendrimers as well as on their use as guests in molecular recognition processes with freely diffusing hosts.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)