Imidazo-containing compounds (e.g., imidazonaphthyridines, imidazopyridines, imidazoquinolines, and imidazote-trahydroquinolines) with an alkoxy substituent at the 1-position, pharmaceutical compositions containing the compounds and methods of use of these compounds as immunomodulators, for inducing cytokine biosynthesis in animals and in the treatment of diseases including viral and neoplastic diseases are disclosed.