Poly(2-methoxyaniline-5-sulfonic acid) (PMAS) is a water-soluble derivative of polyaniline that carries negatively charged sulfonate groups. This self-doped conducting polymer also behaves like a polyelectrolyte that can subsequently function as a dopant in polyaniline (PAn). The chemical synthesis of PAn/PMAS is presented describing the preparation of a highly stable composite dispersion. TEM images reveal a mixture of well-defined nanofibres and nanoparticles with diameters between 20 and 100 nm. The UV vis spectra of i the PAn/PMAS composite in water and in alkaline media indicate that both PAn and PMAS are present in the composite. Electrochemical studies show that both of the conducting polymer components are capable of undergoing oxidation and reduction. The novel PAn/PMAS nanocomposite has enhanced electrical conductivity and stability compared to PAn/HCl nanofibres prepared under equivalent conditions, making i it a promising material for applications in areas such as batteries, electronic textiles, electrochromics, and chemical sensors.