Abstract: Micro-supercapacitors are a new class of high-power miniaturized electrochemical energy-storage devices, which not only offer a balanced energy and power density, bridging the gap between thin-film batteries and electrolytic capacitors, but can also be directly integrated with micro-/nano-scale electronic devices to offer sufficient peak power. This review summarizes recent progress in the device configuration and electrode fabrication of micro-supercapacitors, and discusses the main challenges and future possibilities they offer.