opinion: Mr. Chief Justice Burger
  delivered the opinion of the Court.
  We granted certiorari to decide whether a district court may impose summary contempt punishment under Fed. Rule Crim. Proc. 42 (a) when a witness who has been granted immunity, refuses on Fifth Amendment grounds to testify. The Court of Appeals held that in such circumstances a judge cannot dispose of the contempt summarily, but must proceed under Rule 42 (b), which calls for disposition only after notice and hearing, and “a reasonable time for the preparation of the defense.”
  I
  Respondents Wilson and Bryan, along with one Robert Anderson, were charged in separate indictments with separate bank robberies. Respondent Wilson, and Anderson, were charged with armed robbery of a bank in Tuxedo, N. Y. Respondent Bryan, and Anderson, were charged with armed robbery of a bank in Mount Ivy, N. Y. Prior to Anderson’s trial both respondents pleaded guilty to charges against them, but neither was immediately given a final sentence. Sentencing of Wilson was deferred, and, pending a presentence report, Bryan was given a provisional 25-year sentence, as required by 18 U. S. C. §§4208 (b), (c).
  At Anderson’s trial for the two robberies, respondents were summoned as witnesses for the prosecution. When questioned, however, each refused to testify, contending that his answers might incriminate him. The judge then granted them immunity, 18 U. S. C. §§ 6002-6003, and, relying on Goldberg v. United States, 472 F. 2d 513 (CA2 1973), ordered them to answer forthwith. He informed them that as long as they did not lie under oath they could not be prosecuted by reason of any testimony, but that if they continued to refuse to answer he would hold them in contempt. Respondents nevertheless persisted in their refusals, and the judge summarily held them in contempt. Counsel for Wilson, who acted for both respondents, argued for lenient sentences; however, trial counsel made no objection to the summary nature of the contempt citation, nor was any claim made that more time was needed to prepare a defense to the contempt citation.
  Both respondents were then sentenced to six months’ imprisonment, consecutive to any sentences imposed for the bank robberies. The judge made it clear that he would consider reducing the contempt sentences, or eliminating them completely, if respondents decided to testify. When counsel pointed out that a presentence study was being prepared on Bryan the judge responded: “I am going to impose the maximum . . . with the deliberate intention of revising that sentence to what might be appropriate in light of the very study that is going to be made.” App. 33.
  The trial proceeded, but without Bryan’s testimony the evidence against Anderson on the Mount Ivy robbery was such that at the end of the Government’s case the judge granted Anderson’s motion for acquittal. The jury was unable to reach a verdict on the Tuxedo robbery. At a later trial Anderson was convicted of that robbery.
  Respondents appealed their contempt convictions. The Court of Appeals rejected the claim that their Fifth Amendment rights would have been violated by compelling them to testify after they had been granted immunity, but it accepted their contention that use of the summary contempt power was improper, and it remanded for proceedings under Rule 42 (b). 488 F. 2d 1231 (CA2 1973). The court reasoned that “[i]f . . . counsel had been given ‘a reasonable time for the preparation of the defense,’ Fed. R. Crim P. Rule 42 (h), she might have marshalled and presented facts in mitigation of the charge.” Id., at 1234.
  In requiring Rule 42 (b) disposition the Court of Appeals considered itself bound by its own previous decisions, and by this Court’s decision in Harris v. United States, 382 U. S. 162 (1965). In a previous case the Court of Appeals had held:
  “Summary disposition is thus available only when immediate punishment is necessary to put an end to acts disrupting the proceedings, such as threats to the judge, disturbances in the courtroom or insolence before the court. It is not a remedy to be used in a case like this where the contempt consists of no more than orderly refusal in the absence of the jury to answer a question on Fifth Amendment grounds . . . .” United States v. Pace, 371 F. 2d 810, 811 (CA2 1967).
  In another case the Court of Appeals had interpreted the language of our Harris decision to require that “[a]bsent . . . disruptive conduct, which affronts the dignity of the court, a hearing pursuant to Rule 42 (b) is required to explore possible exculpatory or mitigating circumstances.” United States v. Marra, 482 F. 2d 1196, 1200 (CA2 1973). In the Court of Appeals’ view only a disorderly or obstreperous interference with court proceedings provides an occasion for use of the summary contempt power. -. Id., at 1201-1202.
  Because of the importance of this issue in the conduct of criminal trials, and because the view of the Court of Appeals for the Second Circuit apparently conflicts with that of the Court of Appeals for the First Circuit, Baker v. Eisenstadt, 456 F. 2d 382, cert. denied, 409 U. S. 846 (1972), we granted certiorari. 416 U. S. 981 (1974). We reverse.
  II
  Respondents’ refusals to answer, although not delivered disrespectfully, plainly fall within the express language of Rüle 42 (a), and constitute contemptuous conduct. Rule 42 (a) was never intended to be limited to situations where a witness uses scurrilous language, or threatens or creates overt physical disorder and thereby disrupts a trial. All that is necessary is that the judge certify that he “saw or heard the conduct constituting the contempt and that it was committed in the actual presence of the court.” Respondents do not contest that these requirements are met here. Indeed, here each refusal was in the context of a face-to-face encounter between the judge and respondents. See Illinois v. Allen, 397 U. S. 337 (1970); Cooke v. United States, 267 U. S. 517 (1925).
  The refusals were contemptuous of judicial authority because they were intentional obstructions of court proceedings that literally disrupted the progress of the trial and hence the orderly administration of justice. Yates v. United States, 227 F. 2d 844 (CA9 1955). Respondents’ contumacious silence, after a valid grant of immunity followed by an explicit, unambiguous order to testify, impeded the due course of Anderson’s trial perhaps more so than violent conduct in the courtroom. Violent disruptions can be cured swiftly by bodily removing the offender from the courtroom, or by physical restraints, Illinois v. Allen, supra; see Ex parte Terry, 128 U. S. 289 (1888), and the trial may proceed. But as this case demonstrates, a contumacious refusal to answer not only frustrates the inquiry but can destroy a prosecution. Here it was a prosecution; the same kind of contumacious conduct could, in another setting, destroy a defendant’s ability to establish a case.
  The face-to-face refusal to comply with the court’s order itself constituted an affront to the court, and when that kind of refusal disrupts and frustrates an ongoing proceeding, as it did here, summary contempt must be available to vindicate the authority of the court as well as to provide the recalcitrant witness with some incentive to testify. In re Chiles, 22 Wall. 157, 168 (1875). Whether such incentive is necessary in a particular case is a matter the Rule wisely leaves to the discretion of the trial court.
  Our conclusion that summary contempt is available under the circumstances here is supported by the fact that Rule 42 has consistently been recognized to be no more than a restatement of the law existing when the Rule was adopted, Bloom v. Illinois, 391 U. S. 194, 209 (1968); Notes of the Advisory Committee on Rule 42 (a), 18 U. S. C. App. p. 4513; Cooke v. United States, 267 U. S. 517 (1925), and the law at that time allowed summary punishment for refusals to testify, Hale v. Henkel, 201 U. S. 43 (1906); Nelson v. United States, 201 U. S. 92 (1906); Blair v. United States, 250 U. S. 273 (1919). See Ex parte Hudgings, 249 U. S. 378, 382 (1919); Brown v. Walker, 161 U. S. 591 (1896), and cases cited therein, cf. Ex parte Kearney, 7 Wheat. 38 (1822); In re Savin, 131 U. S. 267 (1889).
  Ill
  The Court of Appeals considered itself bound by language in Harris v. United States, 382 U. S. 162 (1965), to hold Rule 42 (a) inapplicable to the facts here. The crucial difference between the cases, however, is that Harris did not deal with a refusal to testify which obstructed an ongoing trial. In Harris a witness before a grand jury had been granted immunity, 18 U. S. C. § 6002, and nevertheless refused to answer certain questions. The witness was then brought before a District Judge and asked the same questions again. When he still refused to answer, the court summarily held him in contempt. We held in that case that summary contempt was inappropriate because there was no compelling reason for an immediate remedy.
  A grand jury ordinarily deals with many inquiries and cases at one time, and it can rather easily suspend action on any one, and turn to another while proceedings under Rule 42 (b) are completed. We noted in Harris that “swiftness was not a prerequisite of justice .... Delay necessary for a hearing would not imperil the grand jury proceedings.” 382 U. S., at 164. Trial courts, on the contrary, cannot be expected to dart from case to case on their calendars any time a witness who has been granted immunity decides not to answer questions. In a trial, the court, the parties, witnesses, and jurors are assembled in the expectation that it will proceed as scheduled. Here the District Judge pointed out this problem when defense counsel asked for a continuance; he said: “I think we cannot delay this trial. I cannot delay it. I have many other matters that are equally important to the people concerned in those cases which are following.” Delay under Rule 42 (b) may be substantial, and all essential participants in the trial may no longer be readily available when a trial reconvenes. In Harris this Court recognized these problems in noting that summary punishment may be necessary where a “refusal [is] ... an open, serious threat to orderly procedure.” 382 U. 8., at 165. A refusal to testify during a trial may be such an open, serious threat, and here it plainly constituted a literal “breakdown” in the prosecution’s case.
  IV
  In an ongoing trial, with the judge, jurors, counsel, and witnesses all waiting, Rule 42 (a) provides an appropriate remedial tool to discourage witnesses from contumacious refusals to comply with lawful orders essential to prevent a breakdown of the proceedings. Where time is not of the essence, however, the provisions of Rule 42 (b) may be more appropriate to deal with contemptuous conduct. We adhere to the principle that only “ ‘[t]he least possible power adequate to the end proposed’ ” should be used in contempt cases, Anderson v. Dunn, 6 Wheat. 204, 231 (1821). See Taylor v. Hayes, 418 U. S. 488, 498 (1974). As with all power, the authority under Rule 42 (a) to punish summarily can be abused; the courts of appeals, however, can deal with abuses of discretion without restricting the Rule in contradiction of its express terms, and without unduly limiting the power of the trial judge to act swiftly and firmly to prevent contumacious conduct from disrupting the orderly progress of a criminal trial.
  Reversed.
  Rule 42 (a) provides:
  “(a) Summary Disposition.
  “A criminal contempt may be punished summarily if the judge certifies that he saw or heard the conduct constituting the contempt and that it was committed in the actual presence of the court. The order of contempt shall recite the facts and shall be signed by the judge and entered of record.”
  Rule 42 (b) provides:
  “(b) Disposition Upon Notice and Hearing.
  “A criminal contempt except as provided in subdivision (a) of this rule shall be prosecuted on notice. The notice shall state the time and place of hearing, allowing a reasonable time for the preparation of the defense, and shall state the essential facts constituting the criminal contempt charged and describe it as such. The notice shall be given orally by the judge in open court in the presence of the defendant or, on application of the United States attorney or of an attorney appointed by the court for that purpose, by an order to show cause or an order of arrest. The defendant is entitled to a trial by jury in any case in which an act of Congress so provides. He is entitled to admission to bail as provided in these rules. If the contempt charged involves disrespect to or criticism of a judge, that judge is disqualified from presiding at the trial or hearing except with the defendant’s consent. Upon a verdict or finding of guilt the court shall enter an order fixing the punishment.”
  In the Court of Appeals respondents contended that the immunity granted was not coextensive with the scope of the Fifth Amendment privilege against self-incrimination. Kastigar v. United States, 406 U. S. 441, 449 (1972). The Court of Appeals ruled that respondents had not raised the claim in a proper fashion, and respondents did not seek review of that conclusion. Thus no issue concerning the scope of immunity is before us.
  Earlier in the proceeding counsel had requested a continuance to study whether respondents could be compelled to testify after a grant of immunity. App. 5. The trial judge did not allow a continuance. Id., at 6. The Court of Appeals, however, considered that for purposes of appeal the request was sufficient objection to the summary contempt citation. The Government does not contest that ruling so we do not address it.
  For example, the court mentioned that respondent Wilson’s experience suggested the possibility of a psychiatric defense. With time to prepare, the Court of Appeals said, counsel might have "enlarged on the issue of [Wilson’s] mental health, and perhaps shown a relationship between any psychological difficulties and the refusal to serve as a witness.” 488 F. 2d, at 1234r-1235. The record does not support such a defense. On order of the District Court, Wilson had been given a psychiatric examination to determine his competency to stand trial. 18 U. S. C. §4244. He was found competent; however, at the Anderson trial his lawyer argued that the examination revealed family difficulties that may have been a reason for his antisocial behavior. App. 12-13. The District Court agreed that further investigation of Wilson’s psychiatric problems might be helpful for sentencing purposes. Id., at 12, 17. The record does not show that either counsel or the District Court considered for a moment that further psychiatric investigation might provide a defense to the contempt charge. The psychiatric investigation was to determine whether Wilson might more appropriately be placed on probation with psychiatric treatment rather than confined in a prison. Id., at 13, 17.
  Rule 42 applies the contempt power defined in 18 U. S. C. § 401. See Bessette v. W. B. Conkey Co., 194 U. S. 324, 326-327 (1904); Ex parte Robinson, 19 Wall. 505, 510 (1874). That statute provides that a federal court has the power to punish by fine or imprisonment, at its discretion, such contempt of its authority as “[m]isbehavior of any person in its presence or so near thereto as to obstruct the administration of justice.” The predecessor of the statute was enacted to limit the broad power granted by the Judiciary Act of 1789, 1 Stat. 73. Nye v. United States, 313 U. S. 33, 45, 50 (1941). Courts had indiscriminately used the summary contempt power to punish persons for acts that occurred far from the court’s view and which, in truth, could not be considered direct affronts to its dignity, and obstructions of justice. Thus the phrase “in its presence or so near thereto” was intended to apply a geographical limitation on the power. Id., at 50. Misbehavior actually in the face of the court remained punishable summarily, and this Court made it clear that contemptuous actions “actually interrupting the court in the conduct of its business,” id., at 52, were summarily punishable just as “misbehavior in the vicinity of the court disrupting to quiet and order.”. Ibid.
  The trial judge explained to respondents the protection accorded by the grant of immunity and that if they continued in their refusals he would hold them in contempt. He also offered them an opportunity to speak in their own behalf. Groppi v. Leslie, 404 U. S. 496, 501 (1972). Moreover, the judge made it clear that he would consider reducing the sentences if respondents did testify. App. 19-20, 21, 33. In view of this their continued refusals to testify can only be termed intentional.
  In order to constitute an affront to the dignity of the court the judge himself need not be personally insulted. Here the judge indicated he was not personally affronted by respondents’ actions. He said: “I am not angry at Mr. Wilson because he refuses to testify. That is up to him.” App. 14. He also said: “I don’t consider [Bryan] to have a chip on his shoulder towards the Court or towards me.” Id., at 33.
  In Shillitani v. United States, 384 U. S. 364, 371 n. 9 (1966), we said:
  “[T]he trial judge [should] first consider the feasibility of coercing testimony through the imposition of civil contempt. The judge should resort to criminal sanctions only after he determines, for good reason, that the civil remedy would be inappropriate.”
  Here, of course, that admonition carries little weight because at the time they.acted contemptuously both respondents were incarcerated due to their own guilty pleas. Under the circumstances here the threat of immediate confinement for civil contempt would have provided little incentive for them to testify. Contrast, Anglin v. Johnston, 504 F. 2d 1165 (CA7 1974), cert. denied, 420 U. S. 962 (1975). Nevertheless, the careful trial judge made it clear to respondents that if they relented and obeyed his order he would consider reducing their sentences; and he also explained that he would consider other factors in deciding whether to reduce the sentences. Supra, at 312.
  Sources contemporaneous with the adoption of this Rule uniformly indicate that subsection (a) is substantially a restatement of existing law, 6 N. Y. U. School of Law, Institute Proceedings — ' Federal Rules of Criminal Procedure 73 (1946); Dessión, The New Federal Rules of Criminal Procedure: II, 56 Yale L. J. 197, 244 n. 268 (1947); Orfield, Federal Rules of Criminal Procedure, 26 Neb. L. Rev. 570, 613 n. 189 (1947), and was not intended to alter the circumstances in which notice and a hearing are required.
  App. 6.