There has been much recent interest in the development of therapeutic transition metal-based complexes in part fueled by the clinical success of the platinum(II) anticancer drug, cisplatin. Yet known platinum drugs are limited by their high toxicity, severe side-effects, and incidences of drug resistance. Organometallic ruthenium-arene complexes have risen to prominence as a pharmacophore due to the success of other ruthenium drug candidates in clinical trials. In this chapter, we highlight higher order multinuclear ruthenium-arene complexes and their respective investigations as chemotherapeutic agents. We discuss their unique structural properties and the associated biochemical evaluation in the context of anticancer drug design. We also review the structural considerations for the design of these scaffolds and new therapeutic applications that are uncovered for this class of complexes.