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                       [LETTERHEAD OF O'CONNOR CAVANAGH]



                                                                       EXHIBIT 5


                                September 4, 1998


Rural/Metro Corporation
8401 East Indian School Road
Phoenix, Arizona  85251

         RE:      REGISTRATION STATEMENT ON FORM S-8
                  RURAL/METRO CORPORATION

Gentlemen:

         As legal counsel to Rural/Metro Corporation, a Delaware corporation
(the "Company"), we have assisted in the preparation of the Company's
Registration Statement on Form S-8 (the "Registration Statement") to be filed
with the Securities and Exchange Commission on or about September 4, 1998 in
connection with the registration under the Securities Act of 1933, as amended,
of 300,000 shares of the Company's common stock, par value $0.01 per share, (the
"Common Stock") issuable pursuant to the Company's Employee Stock Purchase Plan
(the "ESPP"). The shares of Common Stock issuable pursuant to the ESPP are
referred to as the "Shares." The facts, as we understand them, are set forth in
the Registration Statement.

         With respect to the opinion set forth below, we have examined
originals, certified copies, or copies otherwise identified to our satisfaction
as being true copies, only of the following:

         A.       The Second Restated Certificate of Incorporation of the
                  Company, as filed with the Secretary of State of the State of
                  Delaware as amended through the date hereof;

         B.       The Bylaws of the Company, as amended through the date hereof;

         C.       Resolutions of the Board of Directors of the Company dated
                  September 12, 1997, reserving an aggregate of 300,000 shares
                  of the Company's Common Stock for issuance pursuant to the
                  ESPP; and
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O'CONNOR CAVANAGH

Rural/Metro Corporation
September 4, 1998
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         D. The Registration Statement.

         Subject to the assumptions that (i) the documents and signatures
examined by us are genuine and authentic and (ii) the persons executing the
documents examined by us have the legal capacity to execute such documents, and
subject to the further limitations and qualifications set forth below, it is our
opinion that the Shares, when issued and sold in accordance with the terms of
the ESPP, will be validly issued, fully paid and nonassessable.

         Please be advised that we are members of the State Bar of Arizona, and
our opinion is limited to the legality of matters under the laws of the State of
Arizona and the General Corporation Laws of the State of Delaware. Further, our
opinion is based solely upon existing laws, rules and regulations, and we
undertake no obligation to advise you of any changes that may be brought to our
attention after the date hereof.

         We hereby expressly consent to any reference to our firm in the
Registration Statement, inclusion of this Opinion as an exhibit to the
Registration Statement, and to the filing of this Opinion with any other
appropriate governmental agency.

               Very truly yours,



               /s/ O'CONNOR, CAVANAGH, ANDERSON, KILLINGSWORTH & BESHEARS, P.A.