Synthetic routes to semiconductor nanocrystallites have become of particular interest since nanoparticle devices have been constructed. The route reported here for CdSe uses a single source in tri-n-octylphosphine oxide instead of the hazardous metal alkyls conventionally employed. The characterization of the nanocrystallites (see figure) shows that they are crystalline, approximately spherical, and close to monodispersed.