Piezoelectric fans are investigated as a cooling technology for the thermal management of electronic devices. Flow visualization experiments are conducted to better understand the physics of fan operation. Prototypes of the fans are built and tested to assess their feasibility and cooling performance and determine optimal locations for the fans. An enclosure the size of a cellular phone and a commercially available laptop computer are used to demonstrate the cooling feasibility of the fans. Piezoelectric fans are found to offer significant localized cooling, exceeding enhancements in convective heat transfer coefficients of 100%, while exhibiting low power consumption, minimal noise, and small dimensions. Performance metrics for piezoelectric fans should be based on heat transfer characteristics, such as the percent increase in the heat transfer coefficient of the system. Optimization techniques that maximize the electromechanical coupling factor (EMCF) can be used to design efficient fans.