An original one-step preparation of single-crystal silver nanowires in hexagonal mesoporous silica is presented. The silver precursor, silver nitrate, is reduced in ethylene glycol (EG). This procedure avoids thermal treatments which can lead to phase segregation. The absorbance spectrum of the resulting hybrid material exhibits a transverse resonance plasmon peak near 360 nm whereas the longitudinal oscillation is shifted to the near-infrared region at about 1500 nm. (C) 2003 Elsevier Science Ltd. All rights reserved.