In No. 78-1871, Prank W. Snepp III seeks review of a judgment enforcing an agreement that he signed when he accepted employment with the Central Intelligence Agency (CIA). He also contends that punitive damages are an inappropriate remedy for the breach of his promise to submit all writings about the Agency for prepublication review. In No. 79-265, the United States conditionally cross petitions from a judgment refusing to find that profits attributable to Snepp’s breach .are impressed with a constructive trust. We grant the petitions for certiorari in order to correct the judgment from which both parties seek relief.
I
Based on his experiences as a CIA agent, Snepp published a book about certain CIA activities in South Vietnam. Snepp published the account without submitting it to the Agency for prepublication review. As an express condition of his employment with the CIA in 1968, however, Snepp had *508executed an agreement promising that he would “not . . . publish . . . any information or material relating to the Agency, its activities or intelligence activities generally, either during or after the term of [his] employment . . . without specific prior approval by the Agency.” App. to Pet. for Cert, in No. 78-1871, p. 59a. The promise was an integral part of Snepp’s concurrent undertaking “not to disclose any classified information relating to the Agency without proper authorization.” Id., at 58a.1 Thus, Snepp had pledged not to divulge classified information and not to publish any information without prepublication clearance. The Government brought this suit to enforce Snepp’s agreement. It sought a declaration that Snepp had breached the contract, an injunction requiring Snepp to submit future writings for prepublication review, and an order imposing a constructive trust for the Government’s benefit on all profits that Snepp might earn from publishing the book in violation of his fiduciary obligations to the Agency.2
The District Court found that Snepp had “willfully, deliberately and surreptitiously breached his position of trust with the CIA and the [1968] secrecy agreement” by publishing his book without submitting it for prepublication review. 456 F. Supp. 176, 179 (ED Ya. 1978). The court also found that Snepp deliberately misled CIA officials into believing that he would submit the book for prepublication clearance. Finally, the court determined as a fact that publication of the book had “caused the United States irreparable harm and loss.” *509Id., at 180. The District Court therefore enjoined future breaches of Snepp’s agreement and imposed a constructive trust on Snepp’s profits.
The Court of Appeals accepted the findings of the District Court and agreed that Snepp had breached a valid contract.3 It specifically affirmed the finding that Snepp’s failure to submit his manuscript for prepublication review had inflicted “irreparable harm” on intelligence activities vital to our national security. 595 F. 2d 926, 935 (CA4 1979). Thus, the court upheld the injunction against future violations of Snepp’s prepublication obligation. The court, however, concluded that the record did not support imposition of a constructive trust. The conclusion rested on the court’s percep*510tion that Snepp had a First Amendment right to publish unclassified information and the Government’s concession— for the purposes of this litigation — that Snepp’s book divulged no classified intelligence. Id., at 935-936.4 In other words, the court thought that Snepp’s fiduciary obligation extended only to preserving the confidentiality of classified material. It therefore limited recovery to nominal damages and to the possibility of punitive damages if the Government — in a jury trial — could prove tortious conduct.
Judge Hoffman, sitting by designation, dissented from the refusal to find a constructive trust. The 1968 agreement, he wrote, “was no ordinary contract; it gave life to a fiduciary relationship and invested in Snepp the trust of the CIA.” Id., at 938. Prepublication clearance was part of Snepp’s undertaking to protect confidences associated with his trust. Punitive damages, Judge Hoffman argued, were both a speculative and inappropriate remedy for Snepp’s breach. We agree with Judge Hoffman that Snepp breached a fiduciary obligation and that the proceeds of his breach are impressed with a constructive trust.
II
Snepp’s employment with the CIA involved an extremely high degree of trust. In the opening sentence of the agreement that he signed, Snepp explicitly recognized that he was entering a trust relationship.5 The trust agreement specifi*511cally imposed the obligation not to publish any information relating to the Agency without submitting the information for clearance. Snepp stipulated at trial that — after undertaking this obligation — he had been “assigned to various positions of trust” and that he had been granted “frequent access to classified information, including information regarding intelligence sources and methods.” 456 F. Supp., at 178.6 Snepp published his book about CIA activities on the basis of this background and exposure. He deliberately and surreptitiously violated his obligation to submit all material for prepublication review. Thus, he exposed the classified information with which he had been entrusted to the risk of disclosure.
Whether Snepp violated his trust does not depend upon whether his book actually contained classified information. The Government does not deny — as a general principle— Snepp’s right to publish unclassified information. Nor does it contend — at this stage of the litigation — that Snepp’s book contains classified material. The Government simply claims that, in light of the special trust reposed in him and the agreement that he signed, Snepp should have given the CIA an opportunity to determine whether the material he proposed to publish would compromise classified information or sources. Neither of the Government’s concessions undercuts its claim that Snepp’s failure to submit to prepublication review was a breach of his trust.
Both the District Court and the Court of Appeals found that a former intelligence agent’s publication of unreviewed material relating to intelligence activities can be detrimental *512to vital national interests even if the published information is unclassified. When a former agent relies on his own judgment about what information is detrimental, he may reveal information that the CIA — with its broader understanding of what may expose classified information and confidential sources — could have identified as harmful. In addition to receiving intelligence from domestically based or controlled sources, the CIA obtains information from the intelligence services of friendly nations7 and from agents operating in foreign countries. The continued availability of these foreign sources depends upon the CIA’s ability to guarantee the security of information that might compromise them and even endanger the personal safety of foreign agents.
Undisputed evidence in this case shows that a CIA agent’s violation of his obligation to submit writings about the Agency for prepublication review impairs the CIA’s ability to perform its statutory duties. Admiral Turner, Director of the CIA, testified without contradiction that Snepp’s book and others like it have seriously impaired the effectiveness of American intelligence operations. He said:
“Over the last six to nine months, we have had a number of sources discontinue work with us. We have had more sources tell us that they are very nervous about continuing work with us. We have had very strong complaints from a number of foreign intelligence services with whom we conduct liaison, who have questioned whether they should continue exchanging information with us, for fear it will not remain secret. I cannot esti*513mate to you how many potential sources or liaison arrangements have never germinated because people were unwilling to enter into business with us.” 456 F. Supp., at 179-180.8
In view of this and other evidence in the record, both the District Court and the Court of Appeals recognized that Snepp’s breach of his explicit obligation to submit his material— classified or not — for prepublication clearance has irreparably harmed the United States Government. 595 F. 2d, at 935; 456 F. Supp., at 180.9
*514Ill
The decision of the Court of Appeals denies the Government the most appropriate remedy for Snepp’s acknowledged wrong. Indeed, as a practical matter, the decision may well leave the Government with no reliable deterrent against similar breaches of security. No one disputes that the actual damages attributable to a publication such as Snepp’s generally are unquantifiable. Nominal damages are a hollow alternative, certain to deter no one. The punitive damages recoverable after a jury trial are speculative and unusual. Even if recovered, they may bear no relation to either the Government’s irreparable loss or Snepp’s unjust gain.
The Government could not pursue the only remedy that the Court of Appeals left it10 without losing the benefit of the bargain it seeks to enforce. Proof of the tortious conduct necessary to sustain an award of punitive damages might force the Government to disclose some of the very confidences that Snepp promised to protect. The trial of such a suit, before a jury if the defendant so elects, would subject the CIA and its *515officials to probing discovery into the Agency’s highly confidential affairs. Rarely would the Government run this risk. In a letter introduced at Snepp’s trial, former CIA Director Colby noted the analogous problem in criminal cases. Existing law, he stated, “requires the revelation in open court of confirming or additional information of such a nature that the potential damage to the national security precludes prosecution.” App. to Pet. for Cert, in No. 78-1871, p. 68a. When the Government cannot secure its remedy without unacceptable risks, it has no remedy at all.
A constructive trust, on the other hand, protects both the Government and the former agent from unwarranted risks. This remedy is the natural and customary consequence of a breach of trust.11 It deals fairly with both parties by conforming relief to the dimensions of the wrong. If the agent secures prepublication clearance, he can publish with no fear of liability. If the agent publishes unreviewed material in violation of his fiduciary and contractual obligation, the trust remedy simply requires him to disgorge the benefits of his faithlessness. Since the remedy is swift and sure, it is tailored to deter those who would place sensitive information at risk. And since the remedy reaches only funds attributable to the *516breach, it cannot saddle the former agent with exemplary damages out of all proportion to his gain. The decision of the Court of Appeals would deprive the Government of this equitable and effective means of protecting intelligence that may contribute to national security. We therefore reverse the judgment of the Court of Appeals insofar as it refused to impose a constructive trust on Snepp’s profits, and we remand the cases to the Court of Appeals for reinstatement of the full judgment of the District Court.
So ordered.
Upon the eve of his departure from the Agency in 1976, Snepp also executed a “termination secrecy agreement.” That document reaffirmed his obligation “never” to reveal “any classified information, or any information concerning intelligence or CIA that has not been made public by CIA . . . without the express written consent of the Director of Central Intelligence or his representative.” App. to Pet. for Cert, in No. 78-1871, p. 61a.
At the time of suit, Snepp already had received about $60,000 in advance payments. His contract with his publisher provides for royalties and other potential profits. 456 F. Supp. 176, 179 (ED Va. 1978).
The Court of Appeals and the District Court rejected each of Snepp’s defenses to the enforcement of his contract. 595 F. 2d 926, 931-934 (CA4 1979); 456 F. Supp., at 180-181. In his petition for certiorari, Snepp relies primarily on the claim that his agreement is unenforceable as a prior restraint on protected speech.
When Snepp accepted employment with the CIA, he voluntarily signed the agreement that expressly obligated him to submit any proposed publication for prior review. He does not claim that he executed this agreement under duress. Indeed, he voluntarily reaffirmed his obligation when he left the Agency. We agree with the Court of Appeals that Snepp’s agreement is an “entirely appropriate” exercise of the CIA Director’s statutory mandate to "protec [t] intelligence sources and methods from unauthorized disclosure,” 50 U. S. C. §403 (d)(3). 595 F. 2d, at 932. Moreover, this Court’s cases make clear that — even in the absence of an express agreement — the CIA could have acted to protect substantial government interests by imposing reasonable restrictions on employee activities that in other contexts might be protected by the First Amendment. CSC v. Letter Carriers, 413 U. S. 548, 565 (1973); see Brown v. Glines, ante, p. 348; Buckley v. Valeo, 424 U. S. 1, 25-28 (1976); Greer v. Spock, 424 U. S. 828 (1976); id., at 844-848 (Fowell, J., concurring); Cole v. Richardson, 405 U. S. 676 (1972). The Government has a compelling interest in protecting both the secrecy of information important to our national security and the appearance of confidentiality so essential to the effective operation of our foreign intelligence service. See infra, at 511— 512. The agreement that Snepp signed is a reasonable means for protecting this vital interest.
The Government's concession distinguished this litigation from United States v. Marchetti, 466 F. 2d 1309 (CA4), cert. denied, 409 U. S. 1063 (1972). There, the Government claimed that a former CIA employee intended to violate his agreement not to publish any classified information. 466 F. 2d, at 1313. Marchetti therefore did not consider the appropriate remedy for the breach of an agreement to submit all material for prepub-lication review. By relying on Marchetti in this litigation, the Court of Appeals overlooked the difference between Snepp’s breach and the violation at issue in -Marchetti.
The first sentence of the 1968 agreement read: “I, Frank W. Snepp, III, understand that upon entering duty with the Central Intelligence *511Agency I am undertaking a position of trust in that Agency of the Government. . . .” App. to Pet. for Cert. in No. 78-1871, p. 58a.
Quite apart from the plain language of the agreement, the nature of Snepp’s duties and his conceded access to confidential sources and materials could establish a trust relationship. See 595 F. 2d, at 939 (Hoffman, J., concurring in part and dissenting in part). Few types of governmental employment involve a higher degree of trust than that reposed in a CIA employee with Snepp’s duties.
Every major nation in the world has an intelligence service. Whatever fairly may be said about some of its past activities, the CIA (or its predecessor the Office of Strategic Services) is an agency thought by every President since Franklin D. Roosevelt to be essential to the security of the United States and — in a sense — the free world. It is impossible for a government wisely to make critical decisions about foreign policy and national defense without the benefit of dependable foreign intelligence. See generally T. Powers, The Man Who Kept the Secrets (1979).
In questioning the force of Admiral Turner’s testimony, Mr. Justice SteveNs’ dissenting opinion suggests that the concern of foreign intelligence services may not be occasioned by the hazards of allowing an agent like Snepp to publish whatever he pleases, but by the release of classified information or simply the disagreement of foreign agencies with our Government’s classification policy. Post, at 522-523. Mr. Justice Stevens’ views in this respect not only find no support in the record, but they also reflect a misapprehension of the concern reflected by Admiral Turner’s testimony. If in fact information is unclassified or in the public domain, neither the CIA nor foreign agencies would be concerned. The problem is to ensure in advance, and by proper procedures, that information detrimental to national interest is not published. Without a dependable prepublication review procedure, no intelligence agency or responsible Government official could be assured that an employee privy to sensitive information might not conclude on his own — innocently or otherwise — that it should be disclosed to the world.
The dissent argues that the Court is allowing the CIA to “censor” its employees’ publications. Post, at 522. Snepp’s contract, however, requires no more than a clearance procedure subject to judicial review. If Snepp, in compliance with his contract, had submitted his manuscript for review and the Agency had found it to contain" sensitive material, presumably— if one accepts Snepp’s present assertion of good intentions — an effort would have been made to eliminate harmful disclosures. Absent agreement in this respect, the Agency would have borne the burden of seeking an injunction against publication. See Alfred A. Knopf, Inc. v. Colby, 509 F. 2d 1362 (CA4), cert. denied, 421 U. S. 992 (1975); United States v. Marchetti, 466 F. 2d 1309 (CA4), cert. denied, 409 U. S. 1063 (1972).
Although both the District Court and the Court of Appeals expressly found otherwise, Mr. Justice Stevens says that “the interest in con*514fidentiality that Snepp’s contract was designed to protect has not been compromised.” Post, at 516-517. Thus, on the basis of a premise wholly at odds with the record, the dissent bifurcates Snepp’s 1968 agreement and treats its interdependent provisions as if they imposed unrelated obligaT tions. Mr. Justice SteveNS then analogizes Snepp’s prepublication review agreement with the Government to a private employee’s covenant not to compete with his employer. Post, at 518-520. A body of private law intended to preserve competition, however, simply has no bearing on a contract made by the Director of the CIA in conformity with his statutory obligation to “protec [t] intelligence sources and methods from unauthorized disclosure.” 50 U. S. C. §403 (d)(3).
Judge Hoffman’s dissent suggests that even this remedy may be unavailable if the Government must bring suit in a State that allows punitive damages only upon proof of compensatory damages. 595 F. 2d., at 940. The Court of Appeals majority, however, held as a matter of federal law that the nominal damages recoverable for any breach of a trust agreement will support an exemplary award. See id., at 936, and n. 10, 937-938.
See id., at 939 (Hoffman, J., concurring in part and dissenting in part). Mr. Justice Stevens concedes that, even in the absence of a written contract, an employee has a fiduciary obligation to protect confidential information obtained during the course of his employment. Post, at 518. He also concedes that all personal profits gained from the exploitation of such information are impressed with a constructive trust in favor of the employer. Post, at 521. In this case, he seems to think that the common law would not treat information as “confidential” unless it were “classified.” See, e. g., post, at 518. We have thought that the common-law obligation was considerably more expansive. See, e. g., Restatement (Second) of Agency §§ 396 (c), 400 and Comment c, 404 and Comments b, d (1958); 5 A. Scott, Trusts § 505 (3d ed. 1967). But since this case involves the breach of a trust agreement that specifically required the prepublication review of all information about the employer, we need not look to the common law to determine the scope of Snepp’s fiduciary obligation.