Pressure-actuated electrical switches are provided that comprise a housing having a slidable piston therein. The slidable piston slides from a first position to a second position and in so doing switches an electrical path from a first electrical contact and a second electrical contact to an electrical path between the first electrical contact and a third electrical contact. Suitable applications of such switches include any application in which a pressure wave is used to actuate an electrical switch. The pressure-actuated electrical switches of the present invention are especially adapted for use in controlling successive detonations in a downhole perforation gun, as explosive gases and pressure waves are used to actuate the slidable piston so as to trigger a subsequent detonation charge. Perforation guns utilizing these pressure-actuated electrical switches and corresponding methods of use are also provided herein.