Vapor grown carbon nanofiber reinforced liquid crystal polymer (LCP) composites were studied. The surface resistivity of LCP was lowered more than 11 orders of magnitude by incorporating 5 wt% of nanofibers. The electromagnetic interference shielding effectiveness (SE) at different frequencies was also studied. The composites were shown to exhibit up to 41 dB of SE. The shielding mechanism of the system was mainly reflection and multiple reflections. The thermal conductivity of the composites showed no significant enhancement with the inclusion of nanofibers. (c) 2004 Elsevier Ltd. All rights reserved.