The preparation of discrete erbium-doped silicon nanoparticles prepared by the co-pyrolysis of disilane and the volatile complex Er(tmhd)(3) (tmhd = 2,2,6,6-tetramethyl-3,5-heptanedionato) is described. The nanoparticles were characterized by transmission electron microscopy, selected area electron diffraction, X-ray dispersive spectroscopy, photoluminescence, and UV-visible absorption spectroscopies. Erbium-doped silicon nanoparticles possess a distinctive dark contrast in the transmission electron microscope, and the presence of erbium is confirmed by X-ray energy dispersive spectroscopy. The mean diameter of the nanoparticle aggregates can be shifted by altering the length of the pyrolysis oven employed. Chacteristic Er3+ near-infrared photoluminescence at 1540 nm is detected in these doped nanoparticles; preliminary excitation and power dependence measurements of this luminescence suggest a carrier-mediated emission mechanism.