Typically, this would involve approaching someone who has aroused suspicion to request identification and/or an explanation of the individual's conduct. The 'suspect's' response gives cause for heightened suspicion, and this, in turn, leads to some further action by the police. The reciprocal interaction continues and eventually escalates to the point where incriminating evidence is discovered. The question, then, is whether the discovery of the evidence was the result of unreasonable interference with the individual's privacy. After an extensive consideration of fourth amendment rights and related court cases, it is suggested that police stopping of a person for a brief period to ask a question or two is not unconstitutional and should not require justification based upon objective criteria unless performed in a manner that would alarm or frighten a reasonable person who has nothing to conceal at the time. In this connection, no distinction should be made between a 'request' to stop and an authoritative command or a mildly physical, enforced stop. Scrutiny for justification should be required only where the manner of the stop constitutes a severe intrusion on the security of the individual. When a suspect will not stop or where further questioning is needed the courts should specifically recognize a right of the police to use force to detain the person on reasonable suspicion. The police should not be permitted to coerce involuntary cooperation, and the extent of the detention allowed should be limited to a brief period at the scene of the stop. In cases where persons refuse to identify themselves or where there is reason to believe that they will not be available for further questioning a procedure should exist that permits the police to bring them before a magistrate to require identification or the posting of security for future appearance when required in aid of an investigation. Footnotes are included.