Measurements of electric field relaxation ha~'e been made on two arylene-vinylene polymers. In a sample of low d.c. conductivity (ca. t0nmhom -~ at room temperature) there is evidence of a relaxation about 10ยฐHz, but the conduction currents are too small for meaningful characterization of the phenomenon at very low frequencies. A sample of moderate d.c. conductivity (ca. 1 ,umho mat room temperature) exhibits a clearly defined relaxing complex electric modulus. The permittivity-frequency dependence shows that this is due to charge carrier migration and neutralization rather than hyperpolarization or interfacial polarization. The conductivity-frequency dependence (as in the less conducting sample) indicates that the carrier movement is better described by a 'hopping' than a "band' model. The temperature dependence of the relaxation frequency (activation energy 0.4 e.v.) is the same as that for the d.c. conductivity, indicating that the activation parameters are descriptive of carrier mobility rather than carrier number. The carrier decay function can be fitted to the empirical expression exp(-t/r) ยฐ5. The phenomenon can be described in a self-consistent manner by a model in which carriers diffuse by a random sequence of intermolecular hops to a relaxation site or deep trap where they become neutralized. On this basis the intermolecular energy barrier (or shallow trap depth) is 0.4e.v. and the carrier diffusion coefficient is about 10 -lยฐ m 2 sec -t at room temperature.