Solid-state cooling devices pump heat against a temperature difference without a liquid or gaseous working fluid, and generally with no moving parts. Several solid-state cooling phenomena are the subject of active research including the Peltier effect, electron tunneling, the magnetocaloric effect, the electrocaloric effect, and the thermoelastic effect. This column provides an overview of solid-state cooling versus conventional vapor cycle and an update of the status of Peltier devices.