The magnitudes of the charges developed on contact‐electrified polymers depend on not only the properties of these materials but also the nature of distant substrates on which the polymers are supported. In particular, image charges induced in conductive substrates can decrease charges on the polymers by arc discharge through the surrounding gas. This mode of charge dissipation occurs on timescales of milliseconds and can be prevented by insulating the sharp edges of the conductive supports. (c) 2013 Wiley-VCH verlag CmbH & Co. KGaA Weinheim