In America, the label 'dangerous' often has been applied to persons whose major threat to society was their offense against the moral or esthetic sensibilities of those in power. In the Revolutionary period, there was relatively little violent crime, but by today's standards punishments tended to be harsh and humiliating. The mentally aberrant were viewed as especially dangerous and treated brutally since their conditions was traced to a devilish infestation. The nonconforming behavior of blacks, often restive under slavery, was regarded as dangerous as well. Today, similar kinds of 'dangerous' ascriptions are applied to criminals, mental patients, and minorities, with similarly unconvincing evidence to justify the treatment such persons often receive. Danger should be determined from a social perspective, not from theological or medical perspectives, and the label should include all forms of individual and group action which threaten serious harm to social perspective, not from theological or medical perspectives, and the label should include all forms of individual and group action which threaten serious harm to society and individuals. Emphasis should shift from 'dangerous' people to 'dangerous' behavior. While individuals and their acts are related, the assumption that a status of dangerousness can be reliably attached to particular persons has been overemphasized. The most meaningful definitions of danger are those which link outcome to source. Acts such as building a defective car and polluting the air of a city should be viewed as 'dangerous.' Today, it is not the individual but the impersonal organizational behemoth that poses the greatest danger to individuals and society. Footnotes are given.