delivered the opinion of the Court.
Transportation-Communication Employees Union, the petitioner, is the bargaining representative of a group *158of railroad employees commonly known as “Telegraphers.” Prior to 1952 these telegraphers were commonly assigned the duty of sending, by telegraph, railroad way bills, manifests and orders prepared by clerks, members of the brotherhood of Railway Clerks. In 1952, however, the respondent here, Union Pacific Railroad Company, installed IBM machines which resulted in a radical change in the workload of the telegraphers and clerks. When the clerical work previously done by the clerks is manually performed on the IBM machines, the machines automatically perform the communications functions previously performed by the telegraphers. As a result, the railroad’s need for telegraphers was practically eliminated and operation of the IBM machines was assigned to members of the clerks’ union. This ease arises out of the dispute over the railroad’s assignment of these jobs to the clerks. The telegraphers’ union, claiming the jobs for its members under its collective bargaining agreement, protested the railroad’s assignment and, in due course, referred its claim to the Railroad Adjustment Board as authorized by § 3 First (i) of the Railway Labor Act.1 Notice of the referral was given to the clerks’ union, which, pursuant to an understanding with the other labor unions, declined to participate in this proceeding on the ground that it had no interest in the matter but stated its readiness to file a *159like proceeding before the Board to protect its members should any of their jobs be threatened.2 The Board then heard and decided the case without considering the railroad’s liability to the clerks under its contract with them, concluded that the telegraphers were entitled to the jobs under their contract, and ordered that the railroad pay the telegraphers who had been idle because of the assignment of the jobs to the clerks. The telegraphers’ union then brought this action in a United States District Court to enforce the Board’s award as authorized by § 3 First (p) of the Act. That court dismissed the case on the ground that the clerks’ union was an indispensable party, and that the telegraphers, though given the opportunity, refused to make it a party. 231 *160F. Supp. 33. Affirming the dismissal, the Court of Appeals pointed out that the Board had failed to carry out its exclusive jurisdictional responsibility to decide the entire dispute with relation to the conflicting claims of the two unions under their respective contracts to have the jobs assigned to their members.3 We granted cer-tiorari in order to settle doubts about whether the Adjustment Board must exercise its exclusive jurisdiction to settle disputes like this in a single proceeding with all disputant unions present. Cf. Whitehouse v. Illinois Cent. R. Co., 349 U. S. 366, 371-372. We hold that it must.
I.
Petitioner contends that it is entirely appropriate for the Adjustment Board to resolve disputes over work assignments in a proceeding in which only one union participates and in which only that union’s contract with the employer is considered. This contention rests on the premise that collective bargaining agreements are to be governed by the same common-law principles which control private contracts between two private parties. On this basis it is quite naturally assumed that a dispute over work assignments is a dispute between an employer and only one union. Thus, it is argued that each collective bargaining agreement is a thing apart from all others and each dispute over work assignments must be decided on the language of a single such agreement considered in isolation from all others.
We reject this line of reasoning. A collective bargaining agreement is not an ordinary contract for the purchase of goods and services, nor is it governed by the same old common-law concepts which control such pri*161vate contracts. John Wiley & Sons v. Livingston, 376 U. S. 543, 550; cf. Steele v. Louisville & N. R. Co., 323 U. S. 192. “. . . [I]t is a generalized code to govern a myriad of cases which the draftsmen cannot wholly anticipate. . . . The collective agreement covers the whole employment relationship. It calls into being a new common law — the common law of a particular industry or of a particular plant.” United Steelworkers of America v. Warrior & Gulf Nav. Co., 363 U. S. 574, 578-579. In order to interpret such an agreement it is necessary to consider the scope of other related collective bargaining agreements, as well as the practice, usage and custom pertaining to all such agreements. This is particularly true when the agreement is resorted to for the purpose of settling a jurisdictional dispute over work assignments.
There are two kinds of these jurisdictional disputes. Both are essentially disputes between two competing unions, not merely disputes between an employer and a single union. The ordinary jurisdictional dispute arises when two or more unions claim the right to perform a job which existed at the time their collective bargaining contracts with the employer were made. In such a situation it would be highly unlikely that each contract could be construed as giving each union the right to be paid for the single job. But the dispute before us now is not the ordinary jurisdictional dispute where each union claims the right to perform a job which existed at the time its collective bargaining agreement was made. Here, though two jobs existed when the collective bargaining agreements were made and though the railroad properly could contract with one union to perform one job and the other union to perform the other, automation has now resulted in there being only one job, a job which is different from either of the former two jobs and which was not expressly contracted to either of the unions. Although only one union can be assigned this *162new job, it may be that the railroad’s agreement with the nonassigned union obligates the railroad to pay it for idleness attributable to such job elimination due to automation. But this does not mean that both unions can, under their separate agreements, have the right to perform the new job or that the Board, once the dispute has been submitted, to it, can postpone determining which union has the right to'the job in the future. By first ordering the railroad to pay one union and then later, in a separate proceeding, ordering it to pay the other union, without ever determining which union has the right to perform the job and thus without ever prejudicing the rights of the other union, the Board abdicates its duty to settle the entire dispute. Yet this is precisely the kind of merry-go-round situation which the petitioner claims is envisaged by the Act, a procedure which certainly does not “provide for the prompt and orderly settlement of all disputes . . . ,” the purpose for which the Adjustment Board was established. § 2 (5). (Emphasis supplied.)
I — I h-i
The railroad, the employees, and the public, for all of whose benefits the Railway Labor Act was written, are entitled to have a fair, expeditious hearing to settle disputes of this nature. And we have said in no uncertain language that the Adjustment Board has jurisdiction to do so. Order of Railway Conductors v. Pitney, 326 U. S. 561, was decided 20 years ago. That case concerned a dispute over which employees should be assigned to do certain railroad jobs — members of the conductors’ union under their contract or members of the trainmen’s union under their contract. In that case a district court, in charge of a railroad in bankruptcy, had entered a judgment in favor of the conductors. We reversed, holding that the Railway Labor Act vested exclusive power in the Adjustment Board to decide that controversy over *163job assignments. It is true that we did not precisely decide there that the Board must bring before it all unions claiming the same jobs for their members, but we did say this:
“We have seen that in order to reach a final decision on that question the court first had to interpret the terms of O. R. C.’s collective bargaining agreements. The record shows, however, that interpretation of these contracts involves more than the mere construction of a ‘document’ in terms of the ordinary meaning of words and their position. . . . For 0. R. C/s agreements with the railroad must be read in the light of others between the railroad and B. R. T. And since all parties seek to support their particular interpretation of these agreements by evidence as to usage, practice and custom, that too must be taken into account and properly understood. The factual question is intricate and technical. An agency especially competent and specifically designated to deal with it has been created by Congress.” Id., at 566-567. (Emphasis supplied.)
Pour years after Pitney we decided Slocum v. Delaware, L. & W. R. Co., 339 U. S. 239. In that case a state court had interpreted collective bargaining contracts between a railroad and the same two unions here and had decided in favor of the clerks. We reversed, and, relying on Pitney, said:
“. . . There we held, in a case remarkably similar to the one before us now, that the Federal District Court in its equitable discretion should have refused ‘to adjudicate a jurisdictional dispute involving the railroad and two employee accredited bargaining agents . . . .’ Our ground for this holding was that the court ‘should not have interpreted the contracts’ but should have left this question for determination *164by the Adjustment Board, a congressionally designated agency peculiarly competent in this field. 326 U. S., at 567-568.” Id., at 243-244. (Emphasis supplied.)
We adhere to our holdings in Pitney and Slocum that the Adjustment Board does have exclusive jurisdiction to hear and determine disputes like this. See also Order of Railway Conductors of America v. Southern R. Co., 339 U. S. 255. Petitioner argues that we are barred from this holding by Whitehouse v. Illinois Cent. R. Co., 349 U. S. 366, decided after Pitney and Slocum. There is some language in Whitehouse which, given one interpretation, might justify an inference against the Adjustment Board’s jurisdiction fully to decide this case in a single proceeding. But in the final analysis the holding in Whitehouse was only that the primary jurisdiction of the Adjustment Board could not be frustrated by a premature judicial action. Cf. Carey v. Westinghouse Elec. Corp., 375 U. S. 261, 265-266. We decline to expand that case beyond its actual holding.
The Adjustment Board has jurisdiction, which petitioner admits, to hear and decide the controversy over the interpretation of the telegraphers’ contract with the railroad as it relates to .the work assignments. And § 3 First (j) provides that “the several divisions of the Adjustment Board shall give due notice of all hearings to the employee or employees and the carrier or carriers involved in any disputes submitted to them.” The clerks’ union was given notice here as it should have been under § 3 First (j). Certainly it is “involved" in this dispute. Without its presence, unless it chooses to default and surrender its claims for its members, neither the Board nor the courts below could determine this whole dispute. As respondent contends, to decide, as the Board has here, that the telegraphers are entitled to be paid for these jobs creates another controversy for the railroad with the *165clerks who have the jobs now. For should the Board’s order be sustained, the railroad would not only have to make back payments to the telegraphers who have done no work but would be compelled to continue to pay two sets of workers — one set being idle. The Adjustment Board, as we said about the National Labor Relations Board in Labor Board v. Radio & Television Broadcast Engineers, 364 U. S. 573, 582-583, can, with its experience and common sense, handle this entire dispute in a satisfactory manner in a single proceeding.
We affirm the judgment of the Court of Appeals in holding that the clerks’ union should be a party before the Board and the courts to this labor dispute over job assignments for its members. The cause should be remanded to the District Court with directions to remand this case to the Board.4 The Board should be directed to give once again the clerks’ union an opportunity to be heard, and, whether or not the clerks’ union accepts this opportunity, to resolve this entire dispute upon consideration not only of the contract between the railroad and *166the telegraphers, but “in the light of . . . [contracts] between the railroad” and any other union “involved” in the overall dispute, an,d upon consideration of “evidence as to usage, practice and custom” pertinent to all these agreements. Order of Railway Conductors v. Pitney, supra, at 567. The Board’s order, based upon such thorough consideration after giving the clerks’ union a chance to be heard, will then be enforceable by the courts.
It is so ordered.
This section provides:
“The disputes between an employee or group of employees and a carrier or carriers growing out of grievances or out of the interpretation or application of agreements concerning rates of pay, rules, or working conditions, . . . shall be handled in the usual manner . . . but, failing to reach an adjustment in this manner, the disputes may be referred by petition of the parties or by either party to the appropriate division of the Adjustment Board with a full statement of the facts and all supporting data bearing upon the disputes.” 44 Stat. 578, as amended, 48 Stat. 1191, 45 U. S. C. § 153 First (i).
Section 3 First (j) of the Act, 45 U. S. C. § 153 First (j), requires the Adjustment Board to “give due notice of all hearings to the employee or employees and the carrier or carriers involved in any disputes submitted to them.” (Emphasis supplied.) Prior to this case it was the policy of the various railroad unions, including the clerks’ and telegraphers’, in work-assignment disputes submitted to the Board, to refuse to give notice of and to prohibit participation in Board proceedings by anyone but the involved railroad and the petitioning union. This policy, followed by the labor members of the Board, resulted in no notice being given to the nonpetitioning union. See Whitehouse v. Illinois Cent. R. Co., 349 U. S. 366, 372. In 1959, after some courts had refuséd to enforce the Board’s awards where it had failed to notify the nonpetitioning union, see, e. g., Order of R. R. Telegraphers v. New Orleans, T. & M. R. Co., 229 F. 2d 59, cert. denied, 350 U. S. 997, the Railway Labor Executives’ Association, composed of the various railroad unions, changed this policy to the extent that notice would henceforth be given to non-petitioning unions. Yet the Railway Labor Executives’ Association prescribed a form-letter response — to be sent by the notified non-petitioning union to the Board — which disavowed any interest in the dispute and declined the opportunity to participate before the Board except in a subsequent and separate proceeding initiated by the nonpetitioning union in the event the Board's decision adversely affected its members’ jobs. The clerks’ union used this form letter to respond to the § 3 First (j) notice in the instant ease.
The Court of Appeals’ controlling opinion is reported at 349 F. 2d 408. A prior opinion which was withdrawn is unofficially reported at 59 L. R. R. M. 2993.
The Court of Appeals in affirming the dismissal of the telegraphers’ union’s petition for enforcement was quite correct in holding that the failure of the clerks to appear before the Board and of the Board to consider the contract between the clerks and the railroad could not be cured merely by joinder of the clerks’ union in the District Court’s enforcement proceeding. The Board had the exclusive jurisdiction to consider the clerks’ contract and any claim they might have asserted under it. At the time, the Court of Appeals had no alternative but to affirm the dismissal by the District Court, for district courts could only “enforce or set aside” the Board’s orders under §3 First (p). They could not remand cases to the Board. This was changed on June 20, 1966, by Pub. L. No. 89-456, §2 (e), 80 Stat. 209, which inserted a new provision, § 3 First (q), empowering district courts to remand proceedings to the Board. In view of the Board’s failure to consider all of the issues and the clerks’ understandable refusal to participate because of the then existing doubt as to whether they could be bound by the Board’s decision, we conclude it appropriate to use this new availability of remand to the Board.