Electrically conductive adhesives are emerging as the best possible alternative to traditional tin/lead soldering. In this work polyaniline (PANI) as powder and as nano-fibres was introduced as filler into epoxy/anhydride matrix to produce isotropic conductive adhesives (ICAs). PANI nano-fibres show uniform dispersion and thus percolation threshold is low. Uniformity and smaller size of nano-fibres help in formation of a strong epoxy network with least hindrance from filler phase. This results in better impact performance of these ICAs. SEM observations show an improved diffusion of nano-PANI into the epoxy matrix. Overall, the properties obtained with PANI nano-filler show a significant improvement when compared to PANI powder of macroscopic dimensions. (C) Koninklijke Brill NV, Leiden, 2011