Transition-metal-containing macromolecules are frontline candidates for the design of energy materials due to the metal center that impacts functionalities such as photoactivity and redox activity. For instance, photoactivity enables solar energy harvesting as well as photo-catalysis to enhance the efficiency of electrochemically-and photo-driven energy technologies. Also, redox activity permits efficient electron transfer between junctions, a property that materials scientists are leveraging in designing better-performing biofuel cells, nanowires, and nano-batteries. These macromolecules, therefore, provide innovative solutions to the impending energy crisis. Here, we use empirical examples to illustrate strategies explored by materials scientists to tackle the energy issue using transition-metal-containing macromolecules.