concurring.*
While I join the Court’s opinions in Nos. 443, 360 and 538, I add a word in Nos. 443 and 360.
In each of these two cases the issue concerns the enforcement of but one promise — the promise to arbitrate in the context of an agreement dealing with a particular subject *570matter, the industrial relations between employers and employees. Other promises contained in the collective bargaining agreements are beside the point unless, by the very terms of the arbitration promise, they are made relevant to its interpretation. And I emphasize this, for the arbitration promise is itself a contract. The parties are free to make that promise as broad or as narrow as they wish, for there is no compulsion in law requiring them to include any such promises in their agreement. The meaning of the arbitration promise is not to be found simply by reference to the dictionary definitions of the words the parties use, or by reference to the interpretation of commercial arbitration clauses. Words in a collective bargaining agreement, rightly viewed by the Court to be the charter instrument of a system of industrial self-government, like words in a statute, are to be understood only by reference to the background which gave rise to their inclusion. The Court therefore avoids the prescription of inflexible rules for the enforcement of arbitration promises. Guidance is given by identifying the various considerations which a court should take into account when construing a particular clause — considerations of the milieu in which the clause is negotiated and of the national labor policy. It is particularly underscored that the arbitral process in collective bargaining presupposes that the parties wanted the informed judgment of an arbitrator, precisely for the reason that judges cannot provide it. Therefore, a court asked to enforce a promise to arbitrate should ordinarily refrain from involving itself in the interpretation of the substantive provisions of the contract.
To be sure, since arbitration is a creature of contract, a court must always inquire, when a party seeks to invoke its aid to force a reluctant party to the arbitration table, whether the parties have agreed to arbitrate the particu*571lar dispute. In this sense, the question of whether a dispute is “arbitrable” is inescapably for the court.
On examining the arbitration clause, the court may conclude that it commits to arbitration any “dispute, difference, disagreement, or controversy of any nature or character.” With that finding the court will have exhausted its function, except to order the reluctant party to arbitration. Similarly, although the arbitrator may be empowered only to interpret and apply the contract, the parties may have provided that any dispute as to whether a particular claim is within the arbitration clause is itself for the arbitrator. Again the court, without more, must send any dispute to the arbitrator, for the parties have agreed that the construction of the arbitration promise itself is for the arbitrator, and the reluctant party has breached his promise by refusing to submit the dispute to arbitration.
In American, the Court deals with a request to enforce the “standard” form of arbitration clause, one that provides for the arbitration of “[a]ny disputes, misunderstandings, differences or grievances arising between the parties as to the meaning, interpretation and application of this agreement Since the arbitration clause itself is part of the agreement, it might be argued that a dispute as to the meaning of that clause is for the arbitrator. But the Court rejects this position, saying that the threshold question, the meaning of the arbitration clause itself, is for the judge unless the parties clearly state to the contrary. However, the Court finds that the meaning of that “standard” clause is simply that the parties have agreed to arbitrate any dispute which the moving party asserts to involve construction of the substantive provisions of the contract, because such a dispute necessarily does involve such a construction.
The issue in the Warrior case is essentially no different from that in American, that is, it is whether the company *572agreed to arbitrate a particular grievance. In contrast to American, however, the arbitration promise here excludes a particular area from arbitration — “matters which are strictly a function of management.” Because the arbitration promise is different, the scope of the court's inquiry may be broader. Here, a court may be required to examine the substantive provisions of the contract to ascertain whether the parties have provided that contracting out shall be a “function of management.” If a court may delve into the merits to the extent of inquiring whether the parties have expressly agreed whether or not contracting out was a “function of management,” why was it error for the lower court here to evaluate the evidence of bargaining history for the same purpose? Neat logical distinctions do not provide the answer. The Court rightly concludes that appropriate regard for the national labor policy and the special factors relevant to the labor arbitral process, admonish that judicial inquiry into the merits of this grievance should be limited to the search for an explicit provision which brings the grievance under the cover of the exclusion clause since “the exclusion clause is vague and arbitration clause quite broad.” The hazard of going further into the merits is amply demonstrated by what the courts below did. On the basis of inconclusive evidence, those courts found that Warrior was in no way limited by any implied covenants of good faith and fair dealing from contracting out as it pleased — which would necessarily mean that Warrior was free completely to destroy the collective bargaining agreement by contracting out all the work.
The very ambiguity of the Warrior exclusion clause suggests that the parties were generally more concerned with having an arbitrator render decisions as to the meaning of the contract than they were in restricting the arbitrator’s jurisdiction. The case might of course be otherwise were the arbitration clause very narrow, or the *573exclusion clause quite specific, for the inference might then be permissible that the parties had manifested a greater interest in confining the arbitrator; the presumption of arbitrability would then not have the same force and the Court would be somewhat freer to examine into the merits.
The Court makes reference to an arbitration clause being the quid pro quo for a no-strike clause. I do not understand the Court to mean that the application of the principles announced today depends upon the presence of a no-strike clause in the agreement.
Mr. Justice Frankfurter joins these observations.
[This opinion applies also to No. 443, United Steelworkers of America v. Warrior & Gulf Navigation Co., post, p. 574, and No. 538, United Steelworkers of America v. Enterprise Wheel & Car Corp., post, p. 593.]