We report here detailed investigation into optimizing the synthesis of chiral polyaniline nanotibers using an oligomer-assisted route. The effect of temperature, monomer concentration, nature of oligomer, and the rate of oxidant addition on the optical properties of the PANI nanofibers have been carefully determined. Our results indicate that the highest chirality is achieved under conditions that promote interaction of the chiral acid with the growing polymer chain. These chiral polyaniline nanofibers are thermally stable up to 90 degrees C and are found to be stable against repeated doping-dedoping cycles. The as-synthesized nanolibers are partially crystalline regardless of their chirality. This partial crystallinity may be responsible for their chemical and thermal stability. (c) 2006 Elsevier Ltd. All rights reserved.