Compounds that change their optical, magnetic, and electrical properties as a function of external stimuli, is an exciting area of study in materials science. We recently reported the first polynuclear cyanometalate complexes that exhibit reversible changes their optical and magnetic properties with temperature (up to 250 K) and light. If this is a general phenomenon, then substitution of the metal ions and ligands present may extend the operable switching temperatures of these materials above 300 K. Current efforts are directed at understanding the factors necessary for tuning the photoresponsive behavior in these clusters and related one-dimensional networks.