For decades, people have sought to harvest energy from natural sources. Lately, climate change has popularized solar or photovoltaic technology, while piezoelectric technology is being developed to power handheld devices, and thermoelectric technology is being explored to convert wasted engine heat into electricity. Written by experts from academia and industry, Energy Harvesting with Functional Materials and Microsystems presents current research and explains the field from a materials and device perspective, with resulting technologies capable of enabling low-power implantable sensors or large-scale electrical grids.