delivered the opinion of the Court.

This case concerns the attempt of the petitioner, Local 11 of the Office Employes International Union, AFL-CIO, to represent for collective bargaining purposes the office-clerical workers employed at the Teamsters *314Building in Portland, Oregon. These office-clerical employees were engaged by the various local unions and affiliates of the International Brotherhood of Teamsters, Chauffeurs, Warehousemen and Helpers of America, AFL. Local 11 filed a series of unfair labor practice complaints with respondent, National Labor Relations Board, charging in substance that the Teamster group1 had interfered with the Local’s effort to organize the office-clerical workers in violation of § 8 (a) of the National Labor Relations Act.2 The primary question is whether with respect to their own employees labor organizations are “employers” within the meaning of § 2 (2) of the Act.3 Since we decide this question in the affirmative a subsidiary question is posed: Whether the Board may, by the application of general standards of classification, refuse to assert any jurisdiction over *315labor unions as a class when they act as employers. The Board here refused to assert any jurisdiction, and the complaints were dismissed. 113 N. L. R. B. 987. The Court of Appeals affirmed, 98 U. S. App. D. C. 335, 235 F. 2d 832. The importance of the jurisdictional questions involved caused us to grant certiorari in the interest of the proper administration of the Act. 352 U. S. 906. We believe the Board erred when it refused to take jurisdiction and thus, in effect, engrafted a blanket exemption upon the Act for all labor unions as employers.

We shall not deal with the merits of the unfair labor practice complaints. As to the jurisdictional question, the findings indicate that there are 23 workers employed by the various Teamster organizations at the Teamsters Building. They are paid by the Teamster group which, excluding the Security Plan Office, forms “an integral part of a multistate enterprise.”4 The trial examiner *316concluded that the Teamster group came within the term “employer” under § 2 (2) of the Act. He further found that their operation was well within the monetary jurisdictional standards set by the Board in Jonesboro Grain Drying Cooperative, 110 N. L. R. B. 481 (1954). While the Board agreed with the examiner’s interpretation of § 2 (2) as to the term “employer,” it held, by a divided vote,5 that since the Teamster group was composed of unions, all engaged in a nonprofit business, the criteria applied to other nonprofit employers should govern. It further concluded “that labor organizations, which, when' engaged in their primary function of advancing employee welfare, are institutions unto themselves within the framework of this country’s economic scheme,” should not “be made subject to any of the standards originated for business organizations.” 113 N. L. R. B., at 991.

h-I

With regard to the jurisdiction of the Board the wording of § 2 (2) of the Act is clear and unambiguous. It says that the term “employer” includes any labor organization “when acting as an employer.” It follows that when a labor union takes on the role of an employer the Act applies to its operations just as it would to any other employer. The Board itself recognized this fact as early *317as 1951 in Air Line Pilots Association, 97 N. L. R. B. 929. There the Air Line Pilots Association was found to be an employer and the Board ordered that an election be held to determine the wishes of that union’s own employees in regard to the selection of appropriate employee bargaining units and a collective bargaining representative. Section 9 of the Act6 was therefore applied to the union as an employer.

The legislative history of § 2 (2) unequivocally supports our conclusion. The Act, before its adoption in 1935, was considered by both the 73d and 74th Congresses.7 On each occasion the bill went into committee with labor unions excluded from the definition of an employer.8 Twice the Senate Committee to which it was referred amended it to include within the category of an employer labor unions when dealing with their own employees. The Committee inserted the words “other than when acting as an employer” after the exclusion of labor organizations from the definition of an employer. The Senate Committee on Education and Labor to which the bill was referred stated in explanation of this alteration:

“The reason for stating that ‘employer’ excludes ‘any labor organization, other than when acting as an employer’ is this: In one sense every labor organization is an employer, it hires clerks, secretaries, and the like. In its relations with its own employees, a labor organization ought to be treated as an employer, and the bill so provides.” (Emphasis added.) S. Rep. No. 1184, 73d Cong., 2d Sess. 4.

*318The bill which became the Act in 1935, S. 1958, 74th Cong., 1st Sess., contained the identical language set forth in italics in the above Senate Report. It is inescapable that the Board has jurisdiction.

II.

The question remains whether the Board may, nevertheless, refuse to assert jurisdiction over labor unions, as a class, when acting as employers. The Board in the face of the clear expression of the Congress to the contrary has exempted labor unions when acting as employers from the provisions of the Act. We believe that such an arbitrary blanket exclusion of union employers as a class is beyond the power of the Board. While it is true that “the Board sometimes properly declines to [assert jurisdiction] stating that the policies of the Act would not be effectuated by its assertion of jurisdiction in that case” (emphasis supplied), Labor Board v. Denver Bldg. Council, 341 U. S. 675, 684 (1951), here the Board renounces jurisdiction over an entire category of employers, i. e., labor unions, a most important segment of American industrial life. It reasons that labor unions are nonprofit organizations. But until this case the Board has never recognized such a blanket rule of exclusion over all nonprofit employers. It has declined jurisdiction on an ad hoc basis over religious, educational, and eleemosynary employers such as a university library, a symphony orchestra, a research laboratory, and a church radio station.9 When the Act was amended in 1947 the Congress was aware of the Board’s general practice of *319excluding nonprofit organizations from the coverage of the Act when these organizations were engaged in noncommercial activities.10 The House of Representatives attempted to give these exclusions specific legislative approval.11 However, the Senate draft of the bill excluded only hospital employers from the Act’s coverage. The Senate version became a part of the Act and the language is the same as that involved here. The joint committee report on which the final enactment was based recited that the activities of nonprofit employers or their employees had been considered as coming within the Act only “in exceptional circumstances and in connection with purely commercial activities.” 12 To place labor unions in this category is entirely unrealistic for the very nature of the excluded nonprofit employers is inherently different from that of labor unions and the reason for such exclusion has no applicability to union activity such as that found here. This is particularly true when we consider the pointed language of the Congress — repeated in Taft-Hartley in 1947 — that unions shall not be excluded when acting as employers. As the dissenting judge in the Court of Appeals points out, “§ 2 (2)’s strikingly particular reference to labor unions sharply differentiates them from non-profit organizations generally . . . .” 98 U. S. App. D. C., at 337, 235 F. 2d, at 834. We do not, therefore, believe that it was within the Board’s discretion to remove unions as employers from the coverage of the Act after Congress had specifically included them therein.

*320It is true that the dollar volume jurisdictional standards adopted by the Board to govern its jurisdiction, Hollow Tree Lumber Co., 91 N. L. R. B. 635 (1950), exclude small employers whose business does not sufficiently affect commerce.13 But its exercise of discretion in the local field does not give the Board the power to decline jurisdiction over all employers in other fields. To do so would but grant to the Board the congressional power of repeal. See also Guss v. Utah Labor Relations Board, 353 U. S. 1, 4 (1957), where the Court refused to pass “upon the validity of any particular declination of jurisdiction by the Board or any set of jurisdictional standards.”

We therefore conclude that the Board’s declination of jurisdiction was contrary to the intent of Congress, was arbitrary, and was beyond its power. The judgment is therefore reversed and the case is remanded to the Court of Appeals for remand to the Board for further proceedings in accordance with this opinion.

It is so ordered.

concurring in part and dissenting in part.

I agree that labor organizations are “employers” under § 2 (2) of the Act with respect to their own employees. I dissent, however, from the Court’s holding that the Board is without power to decline to assert jurisdiction over labor unions as a class. I am of the view that the Board has discretionary authority to decline to do so when the Board determines, for proper reasons, that the policies of the Act would not be effectuated by its assertion of jurisdiction. Cf. Labor Board v. Denver Bldg. Council, 341 U. S. 675, 684; Hotel Association of St. Louis, 92 N. L. R. B. 1388, aff’d, 147 F. Supp. 306; Checker Cab Co., 110 N. L. R. B. 683. However, the declination to assert jurisdiction was rested upon the same grounds relied upon by the Board in declining jurisdiction over nonprofit organizations. These grounds, in my view, are not proper reasons for declining to assert jurisdiction over labor organizations. I would, therefore, remand the case to the Court of Appeals for remand to the Board for reconsideration.