Blends of poly(ether ether ketone) and poly(ether imide) have been produced in the composition range 2-20 wt% poly(ether ether ketone) and dynamic mechanical and dielectric behaviour of these materials have been investigated. A composition dependent oc process was observed using both techniques, the temperature of which increased with increasing poly(ether imide) content. The low temperature relaxation behaviour of poly(ether imide) and the dielectric relaxation time in the glass transition region was found to be affected by the addition of poly(ether ether ketone). The variation of loss and storage permittivities showed that the asymmetric broadening was strongly dependent on the blend composition, indicating a high degree of interaction between the components.