The petitioners are five registered voters of Ward 4 in Boston. Two are Democrats and three are Republicans. They include members of the elected Republican and Democratic ward committees. They seek in the county court (see St. 1967, c. 877, § 6) a writ of mandamus (a) to command the respondent commissioners to apportion Suffolk County into representative districts (the commissioners1) to make Ward 4 a separate district with one representative (instead of combining Ward 4 with Ward 10 as a district with two representatives), and (b) to direct the Secretary of the Commonwealth (the Secretary) to refrain from putting into effect the district designations fixed by the commissioners. A single justice, upon a statement of agreed facts, reserved and reported the case without decision for the determination of the full court.
The commissioners, by St. 1967, c. 877, were charged with assigning (upon the basis of the 1965 State Decennial Census) all of Suffolk County to representative districts and distributing a total of thirty-two representatives among the districts to be designated. The “optimum population per representative” according to the census is 22,063. The commissioners established the districts shown in the margin.2 *619The component wards of each multiple representative district in Boston are geographically contiguous.
For at least thirty-five years prior to 1963, Ward 4 had been a separate representative district. Two Democrats and twelve Republicans were elected from Ward 4 in the seven elections from 1950 to 1962, in all but one instance by close votes. For several years prior to 1963, Ward 10 had been combined with Ward 11 to form the Tenth Suffolk District. From 1950 to 1962 that district had elected only Democrats as representatives, all by substantial margins.
In 1963, a special commission (St. 1963, c. 666) conducted a reapportionment of representative districts for Suffolk County. Four of five members of that special commission were Democrats. Ward 4, theretofore a double representative district, was joined with Ward 10 to form a triple representative district. Each of the three Boston wards which in 1962 had elected a Republican representative, was joined in 1963 with another ward to form a multi-represen-tative district. In addition to the combination of Wards 4 and 10, Ward 3 was then joined with Ward 5, and Ward 9 was combined with Ward 12.
In 1964 and 1966, the representatives elected from the new combined Fourth Suffolk District (Wards 4 and 10) were all Democrats, either elected by substantial margins or without Republican opposition. All persons elected were from Ward 10. None lived in Ward 4.
*620As noted above, the combination of Ward 4 with Ward 10 was continued in 1968, when the present commissioners’ report was filed. Because only thirty-two representatives were assigned to Suffolk County in 1968 (instead of forty as in 1963), the combined Fourth Suffolk District was in 1968 given only two representatives instead of three as in 1963.* *3
The petitioners disclaim any objection to (a) whatever population disparities may exist under the commissioners’ 1968 report,4 and also (b) the division of Boston into twenty-two wards. Accordingly, we do not consider these matters.
The petitioners’ contentions are directed primarily to the commissioners’ failure to establish Ward 4 as a separate district to elect a single representative. They point out that Ward 4 by itself has a population of 20,055, which is much more (and much closer to the “optimum” figure of 22,063) than the population (16,381) of the single representative Second Suffolk District (Charlestown) and about the same as that (20,761) of the Third Suffolk District (Ward 3), which also has a single representative. They contend that there was as much reason for setting up Ward 4 as a single-member district as for making Wards 2 and 3 single-member districts. If the commissioners had done so, Ward 10 (with a population of 23,297), as a single-representative district, would then have been closer to the “optimum” population of 22,063 than Wards 2 and 13 (fn. 2) and nearly as close as Ward 3.
Article 21 of the Articles of Amendment to the Constitution of the Commonwealth, as appearing in art. 71 of the Amendments, provides, among other things, that, after “the number of representatives to which each county shall be entitled” is determined by the general court and after the State Secretary has certified this number to the appropriate *621county board, the “county commissioners ... or, in lieu thereof, such board of special commissioners in each county as may for that purpose be provided by law, shall ... assemble at a shire town of their respective counties, and proceed, as soon as may be, to divide the same into representative districts of contiguous territory and assign representatives thereto, so that each representative in such county will represent an equal number of legal voters, as nearly as may be; and such districts shall be so formed that no town containing less than twelve thousand inhabitants according to said census, no precinct of any other town and no ward of a city shall be divided therefor, nor shall any district be made which shall be entitled to elect more than three representatives. . . . The districts in each county shall be numbered by the board creating the same, and a description of each, with the numbers thereof and the number of legal voters therein, shall be returned by the board” to specified officials (emphasis in quoted language supplied).
In St. 1967, c. 877, § 1, it is stated to be the legislative intent that representatives “shall be apportioned in a fair and nondiscriminatory manner and that the districts shall be so established that they will be as nearly equal in population as is practicable.” In the apportionment, there is to be incorporated “the principle of the so-called ‘one-man, one-vote’ standard laid down by the Supreme Court of the United States in recent decisions.” After discussion of certain special difficulties presented by the 1968 reapportionment, § 1 provides “that although each district cannot possibly be drawn containing exactly the same number of inhabitants, nevertheless any deviation from the population of the perfect district shall be minimal and within reasonable and constitutional bounds, so that all the inhabitants of the commonwealth will be afforded equal protection of the law without any invidious discrimination against any person or group" (emphasis supplied).5
*622The petitioners rely in part upon somewhat general language in earlier decisions of this court. In Attorney Gen. v. Suffolk County Apportionment Commrs. 224 Mass. 598, this court set aside a palpably unfair attempted apportionment. In doing so, it was said (p. 606) that “it is the indubitable design of the Constitution to maintain” what the opinion referred to as “equality of influence in shaping legislation.” Nevertheless, this court recognized that absolute equality of representation is not required (p. 604), that complexities may be created by necessary adherence to town and ward lines and other requirements, and that (p. 606) “[a] wide discretion must of necessity be exercised by the commissioners.” It was stated (p. 607), that the “court would be slow to set aside an apportionment which appeared by any exercise of sound discretion to have followed the requirements of the Constitution and to be an approximation to equality” (emphasis supplied).
In Brophy v. Suffolk County Apportionment Commrs. 225 Mass. 124, 127, the opinion mentioned the existence of “obvious objections which may be urged against combinations of wards into double or triple districts.” Reference to such objections was made again in Graham v. Special Commrs. of Suffolk County, 306 Mass. 237, 246-248. In Vigneault v. Secretary of the Commonwealth, ante, 362, 366, it was suggested that following existing political subdivision Unes (as was done in the circumstances there considered) may “restrict the possibility of partisan gerrymandering.” See Reynolds v. Sims, 377 U. S. 533, 578-579.
In this Commonwealth, the creation of two or three-member districts has not been held to be a violation of con*623stitutional or statutory standards, so long as there has been compliance with other applicable requirements. Indeed, the petitioners recognize that the Massachusetts constitutional requirements (of following “existing ward Unes and population standards”)6 may make necessary the use of multi-member districts in some circumstances (e.g. Ward 18 of Boston with a population of 57,548). See Avery v. Midland County, 390 U. S. 474, 484-486. They bring to our attention, however, cases in other jurisdictions in which there has been discussion of the possibility that multimember districts will be employed to effect unconstitutional discrimination. See Kruidenier v. McCulloch, 258 Iowa, 1121, 1135 (“A legislative scheme which creates single-member districts and multi-member districts in an arbitrary manner would be objectionable” and “might be the result of gerrymandering . . . and, in that event . . . arbitrary and capricious”); Jones v. Falcey, 48 N. J. 25, 33-34; Butcher v. Bloom, 415 Pa. 438, 467-468. The Supreme Court of the United States, on the other hand, has not struck down, as such, any comparable multi-member district. See e.g. Fortson v. Dorsey, 379 U. S. 433, 436-439; Burns v. Richardson, 384 U. S. 73, 88-89; Kilgarlin v. Hill, 386 U. S. 120, 125, fn. 3. See also Lucas v. Colorado Gen. Assembly, 377 U. S. 713, 731-732; WMCA, Inc. v. Lomenzo, 382 U. S. 4 (affirming 238 F. Supp. 916, 926-927, S. D. N. Y.) ; Avery v. Midland County, 390 U. S. 474, 484-486; Mann v. Davis, 245 F. Supp. 241, 244-246 (E. D. Va.) affd. per cur. sub nom. Burnette v. Davis, 382 U. S. 42; Sincock v. Gately, 262 F. Supp. 739, 828-833 (D. Del.); Banzhaf, Multi-Member Electoral Districts 75 Yale L. J. 1309, 1335-1337; note, 79 Harv. L. Rev. 1228, 1258-1261; note, 36 Geo. Wash. L. Rev. 144.
The Massachusetts constitutional and statutory provisions already mentioned and the decisions of this court have *624permitted the assignment of not more than three representatives to one district, where that will facilitate redistricting. See Graham v. Special Commrs. of Suffolk County, 306 Mass. 237, 244-249. See also Attorney Gen. v. Secretary of the Commonwealth, 306 Mass. 25, 39. In the Graham case, in circumstances which seem materially more likely to result in numerical malapportionment than those now before us, the action of the commissioners (there, in failing to employ multi-member districts) was held (p. 249) not to be “so unreasonable as to invalidate the division and assignment made by them.”
. We have weighed the petitioners’ contentions in effect (1) that the commissioners, reasonably and without violation of any constitutional or statutory provision, could have made Ward 4 and Ward 10 separate one-member districts; (2) that Wards 2 and 3, although having a population comparable to that of Ward 4, were made separate single-member districts; and (3) that there is some inconsistency between the commissioners’ action (fn. 3, supra) in separating Wards 3 and 5 (combined in 1963) and their 1968 action leaving Wards 4 and 10 together. These, however, are matters of a general type which our decisions, already cited, have treated as calling for the exercise of the commissioners’ judgment.
The apportionment process is primarily a matter for legislative consideration. If the process has been carried out reasonably and without arbitrary conduct, this court has not interfered with the judgment of those entrusted with the task by the Legislature, and has recognized that the commissioners have a substantial range of discretion in matters such as here are criticised. Every reasonable presumption has been made in favor of the commissioners’ report. See Brophy v. Suffolk County Apportionment Commrs. 225 Mass. 124, 128-129; Attorney Gen. v. Secretary of the Commonwealth, 306 Mass. 25, 34-35. We think the agreed facts insufficient to establish that the commissioners have exceeded their discretionary powers under the appropriate constitutional and statutory provisions, or that there has *625been "invidious discrimination against any person or group.” See St. 1967, c. 877, § 1.
The petition is to be dismissed.
So ordered.
The commissioners include five Democrats and one Republican. The record does not disclose the party affiliations of the other three commissioners.
Suffolk Population
*619
Ward 3, which in 1963 had been joined with Ward 5 in a two-representative district, was separated from Ward 5 in 1968. Each of these two wards became in 1968 a separate single-member district.
As will be observed (fn. 2), the smallest population per representative is in the Second Suffolk District (Charlestown) with 16,381 persons electing one representative. The largest population per representative is in the Ninth Suffolk District (Ward 13) with 28,852 persons electing one representative.
Chapter 877, § 4, amended G. L. c. 57, § 5, with respect to the commissioners to apportion Suffolk County. As amended, § 5 provided for dividing the county ‘ ‘into representative districts of contiguous territory and . ._. [the assignment of] representatives thereto, so that each representative in *622such county will represent” as nearly as may be “an equal number of inhabitants, according to the [1965 State] census,” subject to the requirement that “such districts shall be so formed that no town containing less than twelve thousand inhabitants according to said census, no precinct of any other town and no ward of a city shall be divided,” and no district shall be so formed that it “shall be entitled to elect more than three representatives.” This court by c. 877, § 6, was given "jurisdiction of any petition for a writ of mandamus relative to the division of a county into representative districts and the assignment of representatives thereto under” G. L. c. 57, § 5, as amended by c. 877, § 4.
The petitioners disclaim any objection to the applicability or constitutionality (presumably under the Constitution of the United States) of the provisions of arts. 21 and 71 of the Amendments to the Constitution of the Commonwealth.