The size and size distribution of silver nanoclusters embedded in soda‐lime glasses (formed by ion irradiation of Ag+–Na+ion‐exchanged waveguides) has been modified by high‐power laser irradiation. Optical transmittance in the visible range is found to increase above the energy thresholdE*=0.3±0.1 J/cm2for &lgr;=532 nm andE*=5±1 J/cm2for &lgr;=1064 nm for pulse lengths of about 10 ns. Cluster size reduction has been observed. Small radii silver nanoclusters are also formed after laser irradiation of ion‐exchanged waveguides. The optical response of the composites has been determined by optical absorption spectroscopy. Transmission electron microscopy, x‐ray photoelectron and Auger electron spectroscopies, and Rutherford backscattering spectrometry have been used to characterize the composites. ©1996 American Institute of Physics.