Dr. Adder is a dark science fiction novel by American writer K. W. Jeter, set in a future where the United States has largely broken down into reluctantly cooperating enclaves run by a wide variety of strongmen and warlords, with a veneer of government control that seems largely interested in controlling technology. Dr. Adder is an artist-surgeon, who modifies sexual organs of his patients to satisfy the weirdest of perversion; he is clearly depicted as a partly criminal, partly counter-cultural figure in a future Los Angeles which anticipates the cyberpunk idea of the Sprawl trilogy.