Exhibit 5.1
                                                                     -----------


                         [Letterhead of ServiceMaster]


                                 July 28, 1997


ServiceMaster Limited Partnership
The ServiceMaster Company Limited Partnership
ServiceMaster Incorporated of Delaware
One ServiceMaster Way
Downers Grove, Illinois  60515

          Re:  Registration of Securities on Form S-3
               Under the Securities Act of 1933
               --------------------------------------

Gentlemen:

          I am Senior Vice President and General Counsel of ServiceMaster
Limited Partnership, a Delaware limited partnership (the "Parent Partnership"),
and The ServiceMaster Company Limited Partnership ("The ServiceMaster Company")
and Vice President and Secretary of ServiceMaster Incorporated of Delaware
("ServiceMaster Incorporated").  In those capacities, I have participated in the
preparation of, and I am familiar with the contents of:

     (i)  the Registration Statement on Form S-3 of the Parent Partnership, The
          ServiceMaster Company and ServiceMaster Incorporated (the
          "Registration Statement"), which is being filed with the Securities
          and Exchange Commission on or about the date of this letter, which
          registers under the Securities Act of 1933 (a) certain debt securities
          which may be issued by The ServiceMaster Company prior to the
          Reincorporation (as described in the Registration Statement) and by
          ServiceMaster Incorporated thereafter (collectively, the "Debt
          Securities," which term includes any guarantee thereof by the Parent
          Partnership), (b) partnership shares which may be issued by the Parent
          Partnership (the "Partnership Shares") prior to the Reincorporating
          Merger (as described in the Registration Statement), (c) shares of
          common stock (the "Merger Shares") of ServiceMaster Incorporated into
          which any Partnership Shares issued under the Registration Statement
          will be converted in the Reincorporating Merger, and (d) shares of
          common stock which ServiceMaster Incorporated may issue after the
          Reincorporating Merger in offerings made under the Registration
          Statement (the "Corporate Shares"), and

     (ii) a proposed Indenture (the "Indenture") between The ServiceMaster
          Company, the Parent Partnership and Harris Trust and Savings Bank, as
          trustee (the "Trustee"), under which The ServiceMaster Company may
          issue Debt Securities in one or more


ServiceMaster Limited Partnership
The ServiceMaster Company Limited Partnership
ServiceMaster Incorporated of Delaware
July 28, 1997
Page 2

 
          series and which provides a mechanism for ServiceMaster Incorporated
          to take the place of The ServiceMaster Company and the Parent
          Partnership in connection with the Reincorporation.

          I have reviewed the resolutions adopted by the Board of Directors of
ServiceMaster Management Corporation in its capacity as the managing general
partner of the Parent Partnership and The ServiceMaster Company (the
"Partnership Board") and resolutions adopted by the Board of Directors of
ServiceMaster Incorporated (the "SMI Board"). Such resolutions, among other
things, (i) authorize the Finance Committee of the Partnership Board to
determine the principal amount of Debt Securities to be issued in each offering
and the price for which those Debt Securities may be sold, (ii) appoint
Authorized Officers who are authorized to act on behalf of the registrants with
respect the matters relevant to the registration, (iii) authorize all or any one
or more of the Authorized Officers to approve the terms of the Indenture
relating to the Debt Securities and the terms of each series of Debt Securities
which may be issued under the Indenture, (iv) authorize the Finance Committee to
authorize the issuance of the Partnership Shares in such number and at such
price and on such other terms as the Finance Committee shall approve, (v)
authorize each Authorized Officer to cause each registrant to take such other
actions as such Authorized Officer determines to be within the scope of the
resolution. Any resolution which shall be approved by the Finance Committee or
any authorization which may be granted by all or any one or more of the
Authorized Officers pursuant to the authority delegated by the Authorizing
Resolutions or authority otherwise exercisable by such Committee or Officer or
Officers is called an "Implementing Authorization" in this letter. I have also
reviewed such other records and documents as I have deemed necessary in order to
enable me to express the opinions stated herein.

          On the basis of the foregoing and subject to the limitations and
assumptions identified in this letter, I am of the opinion that:

     1.   The Parent Partnership and The ServiceMaster Company are each a
          limited partnership validly existing and in good standing under the
          Revised Uniform Limited Partnership Act of the State of Delaware (the
          "Delaware RULPA"). ServiceMaster Incorporated is a corporation validly
          existing and in good standing under the Delaware General Corporation 
          Law.


ServiceMaster Limited Partnership
The ServiceMaster Company Limited Partnership
ServiceMaster Incorporated of Delaware
July 28, 1997
Page 3

 
     2.   The Indenture will constitute a valid and binding obligation of The
          ServiceMaster Company and the Parent Partnership enforceable against
          The ServiceMaster Company and the Parent Partnership in accordance
          with its terms upon the approval of an appropriate Implementing
          Authorization and due execution and delivery by The ServiceMaster
          Company, the Parent Partnership, and the Trustee.

     3.   The Indenture will constitute a valid and binding obligation of
          ServiceMaster Incorporated enforceable against ServiceMaster
          Incorporated in accordance with its terms upon the consummation of the
          Reincorporation, the execution by ServiceMaster Incorporated of a
          supplemental indenture expressly assuming all of the obligations of
          The ServiceMaster Company on all of the Debt Securities and under the
          Indenture, and the compliance with the related requirements in Article
          6 of the Indenture, and the authorization of these actions by the SMI
          Board.

     4.   Debt Securities issued in any series will be legally issued and will
          be binding obligations of The ServiceMaster Company or ServiceMaster
          Incorporated enforceable in accordance with their terms assuming that:
          (a) the conditions contemplated in paragraph 3 of this letter (if such
          series is to be issued by ServiceMaster Incorporated) or in paragraphs
          3 and 4 of this letter (if such series is to be issued by The
          ServiceMaster Company) have been satisfied, (b) the terms of such Debt
          Securities and their issue and sale have been duly established in
          accordance with the Authorizing Resolutions, Article Two of the
          Indenture and an appropriate Implementing Authorization, (c) such Debt
          Securities have been duly executed, authenticated, issued and
          delivered, and (d) The ServiceMaster Company or ServiceMaster
          Incorporated has received the prescribed consideration for the
          issuance of such Debt Securities, all in accordance with the terms and
          conditions of the Indenture, the Authorizing Resolutions and the
          relevant Implementing Authorizations and in the manner contemplated by
          the Registration Statement.

     5.   Any Partnership Shares which may be issued by the Parent Partnership
          in offerings made under the Registration Statement will be validly
          issued by the Parent Partnership assuming (a) the issue and sale of
          the Partnership Shares is duly authorized by an appropriate resolution
          adopted by the Finance Committee, (b) the certificates representing
          the Partnership Shares comply as to form with the Parent Partnership's
          Governing Instruments and the Authorizing Resolutions and bear all
          necessary signatures and authentications, and (c) the Parent
          Partnership has received the prescribed consideration for the
          Partnership Shares. Neither the Parent Partnership's Governing
          Instruments nor the Delaware RULPA


ServiceMaster Limited Partnership
The ServiceMaster Company Limited Partnership
ServiceMaster Incorporated of Delaware
July 28, 1997
Page 4

 
          authorizes any assessment to be made against the owners of the
          Partnership Shares except to the extent authorized by Section 17-607
          of Delaware RULPA.

     6.   In the event that any Partnership Shares are issued prior to the
          Reincorporating Merger in connection with offerings under the
          Registration Statement with respect to which the conditions specified
          in paragraph 5 of this letter are satisfied, then the Merger Shares
          into which those Partnership Shares will be converted in the
          Reincorporating Merger will upon their issuance by ServiceMaster
          Incorporated be validly issued, fully paid and nonassessable.

     7.   Any Corporate Shares which may be issued by ServiceMaster Incorporated
          after consummation of the Reincorporating Merger will be validly
          issued, fully paid and nonassessable assuming that: (i) the issue and
          sale of the Corporate Shares shall be authorized by an appropriate
          Implementing Authorization adopted by the SMI Board, (ii) the
          certificates representing the Corporate Shares comply as to form with
          the By-laws of ServiceMaster Incorporated, the General Corporation Law
          of the State of Delaware and the Authorizing Resolutions and bear all
          necessary signatures and authentications, and (iii) ServiceMaster
          Incorporated has received the prescribed consideration for the
          Corporate Shares.

          The opinions expressed herein regarding enforceability of the
Indenture and any series of Debt Securities are subject to: (i) the effect of
bankruptcy, insolvency, fraudulent conveyance and other similar laws and
judicially developed doctrines in this area such as substantive consolidation
and equitable subordination; (ii) the effect of general principles of equity;
and (iii) other commonly recognized statutory and judicial constraints on
enforceability including statutes of limitations.

          The Parent Partnership's Certificate of Limited Partnership filed with
the Delaware Secretary of State as constituted on the date hereof and the Parent
Partnership's Amended and Restated Partnership Agreement as constituted on the
date hereof are herein called "the Parent Partnership's Governing Instruments."
The Board of Directors and the sole stockholder of ServiceMaster Incorporated
have approved the amendment and restatement of the Certification of
Incorporation of ServiceMaster Incorporated and all other actions necessary to
make such amendment and restatement effective have been taken except for the
filing of such amendment and restatement in Delaware. I have assumed for
purposes of this opinion that such amendment and restatement will be filed in
Delaware and will become effective prior to consummation of the Reincorporating
Merger. All of my opinions assume that the Registration Statement will become


 
ServiceMaster Limited Partnership
The ServiceMaster Company Limited Partnership
ServiceMaster Incorporated of Delaware
July 28, 1997
Page 5


effective under the Securities Act before any Debt Securities, Partnership
Shares, or Corporate Shares covered by the Registration Statement are issued. I
have also made other assumptions which I believe to be appropriate for purposes
of this letter.

     My advice on every legal issue addressed in this letter is based
exclusively on the internal law of Illinois, the Delaware RULPA, the Delaware
General Corporation Law, or the federal law of the United States. The Indenture
provides that the Indenture and the Debt Securities issued under the Indenture
are to be governed by the law of New York, but my advice on every state law
issue with respect to the Indenture provides that the Indenture and the Debt
Securities issued under the Indenture represents my opinion of how that issue
would be resolved by the Illinois state courts if the Indenture and the Debt
Securities issued under the Indenture had instead provided that they were
governed by Illinois internal law and the Illinois state courts applied Illinois
internal law to resolve such issue. I express no opinion whether any relevant
difference exists between the laws upon which my opinions are based and the laws
of New York or any other laws which may actually be used to decide any issue
addressed by this letter. This letter does not cover any law which in my
experience would generally not be considered by lawyers in Illinois for purposes
of the opinions contained in this letter. Without limiting by implication the
generality of the preceding sentence, this opinion does not cover the securities
laws of the state of Illinois or any other jurisdiction. Each reference in this
letter to general principles of equity includes but is not limited to:
principles limiting the availability of specific performance and injunctive
relief; principles which limit the availability of a remedy under certain
circumstances where another remedy has been elected; principles requiring
reasonableness, good faith and fair dealing in the performance and enforcement
of an agreement by the party seeking enforcement; principles which may permit a
party to cure a material failure to perform its obligations; and principles
affording equitable defenses such as waiver, laches and estoppel.

          I hereby consent to the inclusion of this letter as an exhibit to the
Registration Statement and to the reference in each Prospectus included as part
of the Registration Statement to my having issued the opinions expressed herein.


                              Very truly yours,

                              /s/ Vernon T. Squires

                              Vernon T. Squires
                              Senior Vice President and General Counsel