There have been several notable advances in the field of conducting polymer colloids over the past year or so. These include the development of conducting polymer-inorganic oxide nanocomposites, conductive film-forming latexes, various surface-functionalized particles, and a general synthetic route to sterically stabilized polypyrrole dispersions. Given their intense intrinsic coloration, some of these colloids may be useful in immunodiagnostic assays.