In America today, overt acts of discrimination are frowned upon and often dubbed unlawful. Yet social psychology suggests that a powerful unconscious bias may influence the way in which we view and treat members of certain groups. Even absent flagrant discrimination, this implicit prejudice can undermine civil rights laws and efforts at promoting equal opportunity. To what extent does this unconscious bias exist? How accurate are existing measures of bias? Can we reduce this prejudice by bringing its existence to light?