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                                                                   EXHIBIT 10.56


                               FIRST AMENDMENT TO

                   PROVISIONAL WAIVER AND STANDSTILL AGREEMENT


         THIS FIRST AMENDMENT TO PROVISIONAL WAIVER AND STANDSTILL AGREEMENT
(this "First Amendment") is made and entered into as of the 13th day of April,
2000, by the Lenders party to the Credit Agreement identified below and FIRST
UNION NATIONAL BANK, as Agent for the Lenders, and RURAL/METRO CORPORATION, a
corporation organized under the laws of Delaware (the "Borrower").

                              Statement of Purpose

         Pursuant to the Provisional Waiver and Standstill Agreement dated as of
March 14, 2000 (as amended, restated, supplemented or otherwise modified, the
"Waiver Agreement"), the Borrower, the Agent and the Lenders, each a party to
the Amended and Restated Credit Agreement dated as of March 16, 1998 (as amended
by First Amendment dated as of June 30, 1998 and as further amended, restated,
supplemented or otherwise modified, the "Credit Agreement"), agreed to waive the
Acknowledged Defaults provisionally for a period of 30 days after March 14, 2000
and to defer the exercise of remedies during such period, subject to the express
terms and provisions of the Waiver Agreement.

         Pursuant to the terms of the Waiver Agreement, the Borrower agreed,
among other things, to continue negotiations with the Agent and the Lenders to
amend or otherwise restructure the Credit Agreement on or before April 14, 2000.
The Borrower, the Agent and the Lenders are continuing to negotiate but have not
yet reached an agreement on such amendment or restructuring and the Borrower
has, therefore, requested an additional period of time in which to continue such
negotiations.

         The Lenders and the Agent are willing to continue to waive the
Acknowledged Defaults provisionally for an additional period of time and to
defer the exercise of remedies in respect of the Acknowledged Defaults during
such period subject to the express terms and provisions of this First Amendment.
This First Amendment shall be deemed to be one of the Loan Documents under and
pursuant to the Credit Agreement.

         NOW THEREFORE, in consideration of the premises and the mutual
covenants contained herein and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereto
agree as follows:

         1. Effect of Amendment. Except as expressly amended hereby, the Waiver
Agreement, the Credit Agreement and each other Loan Document, shall be and
remain in full force and effect. The amendments granted in this First Amendment
are specific and limited and shall not constitute a modification, acceptance or
waiver of any other provision of the Waiver
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Agreement, the Credit Agreement, the other Loan Documents or any other document
or instrument entered into in connection therewith, or a future modification,
acceptance or waiver of the provisions set forth therein. For avoidance of
doubt, but in no way limiting the scope and breadth of the previous sentences in
this paragraph, each Credit Party hereby reaffirms each of the acknowledgments
and agreements made by it in Sections 1 and 6 of the Waiver Agreement as if each
such acknowledgment and agreement was made as of the date hereof.

         2. Capitalized Terms. All capitalized undefined terms used in this
First Amendment shall have the meanings assigned thereto in the Waiver
Agreement.

         3. Amendment of Waiver Agreement. The Waiver Agreement shall be hereby
amended as follows:

         a. Section 2 shall hereby be amended by deleting Section 2 and
replacing it in its entirety with the following:

                  "Provisional Waiver and Limited Deferral. The Lenders and the
         Agent respectively agree to waive the Acknowledged Defaults
         provisionally and to defer the exercise of any rights or remedies
         arising by reason of Events of Default that have occurred solely as a
         result of the occurrence of the Acknowledged Defaults until that date
         (as so extended and as may be further extended, the "Waiver Maturity
         Date") which is the earliest to occur of (a) July 14, 2000; (b) the
         occurrence of any Event of Default other than (i) the Acknowledged
         Defaults or (ii) any breach of the financial covenants that are the
         subject of the Acknowledged Defaults as of the fiscal quarters ending
         March 31, 2000 and June 30, 2000; (c) any Event of Default (as such
         term is defined in the Senior Note Indenture (as defined below)) that
         shall have occurred under the Indenture dated as of March 16, 1998, by
         and among the Borrower, the subsidiaries acting as Guarantors thereto,
         and the First National Bank of Chicago, as Trustee (the "Senior Note
         Indenture"); or (d) the breach of any of the further conditions or
         agreements provided in the Waiver Agreement as amended by this First
         Amendment, it being agreed that the breach of any such further
         condition or agreement shall constitute an immediate Default and Event
         of Default under the Credit Agreement."

         b. Paragraph 3(a) shall hereby be amended by deleting paragraph 3(a)
and replacing it in its entirety with the following:

                  "The Aggregate Commitment shall hereby be permanently reduced
         to an amount equal to the amount of the Existing Extensions of Credit
         minus any prepayments as provided in paragraph 3(b) below minus the
         amount of any outstanding Letter of Credit which is canceled or not
         renewed pursuant to paragraph 3(c)."

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         c. Paragraph 3(b) shall be amended by deleting paragraph 3(b) and
replacing it in its entirety with the following:

                  "(i) The Aggregate Commitment shall hereafter be further
         reduced and the Existing Loans repaid by an amount equal to: (A) one
         hundred percent (100%) of the gross cash proceeds, net of all
         reasonable costs of sale and taxes paid or payable as a result thereof
         by the Borrower and its Subsidiaries, from the sale or other
         disposition of assets by the Borrower or any of its Subsidiaries from
         and after March 14, 2000 (including any Borrower's or its Subsidiary's
         equity ownership in any Person), (B) one hundred percent (100%) of the
         gross cash proceeds received by the Borrower or any of its Subsidiaries
         in connection with disputes over certain receivables (the "Disputed
         Receivables") with Medicare/Medicaid carriers in Texas, and (C) one
         hundred percent (100%) of the gross cash proceeds received by the
         Borrower or any of its Subsidiaries from any and all receivables from
         their respective business operations in Texas which the Borrower elects
         to shutdown at its option (net of expenses, termination costs, costs of
         professionals and other direct costs related to the shutdown of such
         business operations, which expenses shall include severance and other
         employee-related expenses in respect of the shutdown of such business
         operations and payment of open accounts payable balances in respect of
         such business operations for which services were rendered prior to such
         shutdown); provided that (I) any and all receivables generated by the
         Fort Worth, Texas operations shall be excluded from the requirements
         set forth in this clause (C) and (II) Disputed Receivables shall be
         excluded from the requirements set forth in this clause (C) and subject
         to the requirements set forth in clause (B) above. Notwithstanding the
         foregoing, (X) up to an aggregate amount of two million ($2,000,000)
         dollars of the gross cash proceeds (the "Carve Out") realized upon any
         disposition of assets or shutdown of operations set forth in the
         preceding clauses (A) and (C) shall be exempt from this paragraph
         3(b)(i), and (Y) the Borrower agrees that this provision shall not be
         deemed to permit the sale of assets not otherwise permitted under the
         Credit Agreement. All reductions and prepayments set forth in this
         paragraph shall be made immediately upon receipt of the applicable cash
         proceeds and, for any transactions subject to clause (C) of this
         paragraph 3(b)(i), the identification of any applicable adjustments to
         such proceeds; provided, that all adjustments to any proceeds received
         by the Borrower or its Subsidiaries shall be completed, and the
         applicable amounts turned over to the Lenders within ten (10) Business
         Days after the end of the month in which such funds are received unless
         the Lender Financial Consultant agrees to provide the Borrower
         additional time to complete its adjustments.

                  (ii) The Aggregate Commitment shall, in addition to the other
         reductions set forth in this paragraph 3(b), hereafter be further
         reduced and the Existing Loans repaid at any time that the Borrower's
         and its Subsidiaries' actual ending cash balances as reflected on the
         Borrower's weekly Cash Flow Projection report provided pursuant to
         Section 4(b)(i) below (the "Reported Cash Balance") is greater than ten
         million ($10,000,000) dollars for any two (2) consecutive calendar
         weeks in an amount equal to (A) fifty percent (50%) of the difference
         between (I) the Reported Cash Balance of the calendar week most

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         recently ended minus (II) ten million ($10,000,000) dollars (the
         difference between the Reported Cash Balance of the calendar week most
         recently ended minus ten million ($10,000,000) dollars defined herein
         as the "Excess Cash") until the aggregate amount of the Excess Cash is
         equal to four million ($4,000,000) dollars, and thereafter, (B) ninety
         percent (90%) of the Excess Cash. The foregoing Excess Cash amounts
         shall be due and payable on the date on which the applicable Cash Flow
         Projection report is due."

                  Notwithstanding anything to the contrary in any other Loan
         Document, repayments of Existing Loans in connection with reductions to
         the Aggregate Commitment pursuant to this paragraph 3(b) shall be
         applied to the repayment of the Existing Extensions of Credit in the
         manner and in the order set forth in Section 2.3(b) of the Credit
         Agreement.

         d. Paragraph 3(c) shall hereby be amended by adding the following
sentence to the end of paragraph 3(c):

                  "For the purposes of the Waiver Agreement, as amended hereby,
         a renewal of a Letter of Credit shall include a change of the
         beneficiary of the applicable Letter of Credit if, and only if, the new
         beneficiary is providing the same services as the previous beneficiary
         and all other terms and conditions of the new Letter of Credit are
         identical to the previous Letter of Credit."

         e. Paragraph 3(d) shall hereby be amended by deleting paragraph 3(d)
and replacing it in its entirety with the following:

                  "The Existing Loans shall bear interest at a rate equal to the
         Base Rate plus the Applicable Margin (the "Applicable Base Rate") plus
         two percent (2.0%) per annum (which two percent (2.0%) shall, for the
         purposes hereof, be defined as "Deferred Interest"). Interest accruing
         at the Applicable Base Rate shall be due and payable in arrears on the
         first Business Day of each calendar month commencing on May 1, 2000.
         Deferred Interest shall accrue and be payable as follows: (i) at any
         time that the Reported Cash Balance is greater than ten million
         ($10,000,000) dollars for any two (2) consecutive weeks, the Deferred
         Interest shall be due and payable on the date(s) such weekly Cash Flow
         Projection report is due in an amount equal to the difference between
         (A) the Reported Cash Balance of the calendar week most recently ended
         minus (B) ten million ($10,000,000) dollars, and (ii) all remaining
         accrued but unpaid Deferred Interest shall be due and payable in full
         on the Waiver Maturity Date, if ever; provided, that, each time
         subsequent to the date hereof through the Waiver Maturity Date, the
         Borrower has reduced the amount of the Existing Extensions of Credit by
         no less than five million ($5,000,000) dollars, the Deferred Interest
         that would accrue for the next thirty (30) days shall be waived by the
         Agent and Lenders, it being acknowledged and agreed that any accrued
         but unpaid Deferred Interest up through the date on which the waiver of
         Deferred Interest referred to above becomes applicable shall still be
         due and payable in accordance with the terms hereof. In addition, from
         and after the Waiver Maturity Date, and at the

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         option of Required Lenders, all amounts due under the Loan Documents
         shall bear interest at a rate equal to two percent (2.0%) in excess of
         the rate set forth in this paragraph 3(d).

         f. Section 4 shall hereby be amended by deleting Section 4(b)(v) in its
entirety and replacing it with the following:

                  "No later than the last day of each calendar week, a cash flow
         projection (the "Cash Flow Projection") for the Borrower and its
         Subsidiaries, prepared on a "rolling basis" for the next succeeding
         thirteen (13) week period, which shall be in the form of, and contain
         the information set forth in, the report attached hereto as Exhibit
         "A";

         g. Section 4 shall hereby be further amended by adding the following
clause (vii) to the end of Section 4(b):

                  "; and no later than May 15, 2000, a detailed schedule
         identifying on a preliminary basis the anticipated costs and expenses
         and net realizable value of the receivables and sale of any assets in
         connection with the voluntary shutdown of the Borrower's and
         Subsidiaries' respective operations."

         h. Section 4 shall hereby be further amended by adding the following
paragraphs (g), (h), (i) and (j) to the end of Section 4:

                  "(g) Each calendar week, the Borrower and its Subsidiaries
         shall maintain a cash balance of no less than fifty percent (50%) of
         the projected cash balance for such week set forth in the Cash Flow
         Projection provided on the last day of the previous calendar week.

                  (h) The amount of disbursements in each two (2) consecutive
         week period by the Borrower and its Subsidiaries shall not exceed by
         more than five percent (5%) the amount of disbursements for such two
         (2) week period set forth in the applicable Cash Flow Projection
         reports; provided, that the Borrower and its Subsidiaries may use the
         Carve Out or any Excess Cash that is not required to be turned over to
         the Lenders to make any additional disbursements.

                  (i) The Borrower and its Subsidiaries shall maintain a
         positive Consolidated operating income, except for restructuring
         charges taken in accordance with GAAP, as reflected in the financial
         statements prepared pursuant to Section 4(b)(ii) above.

                  (j) No later than April 30, 2000, the Borrower shall have
         engaged a financial advisor (the "Financial Advisor") to assist the
         Borrower in exploring strategic alternatives. The Agent and the Lenders
         shall be provided with an executed copy of the engagement letter
         between the Borrower and the Financial Advisor promptly upon such
         letter's execution. The Agent and Lenders shall, in addition, shall be
         provided upon request reasonable access to the Financial Advisor and
         shall be further provided with copies of all

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         reports, analyses, and other work-product of such Financial Advisor
         when such information is delivered to the Borrower."

         4. Release. Each Credit Party, on behalf of itself and any Person
claiming by, through, or under such Credit Party, acknowledges that it has no
claim, counterclaim, setoff, action or cause of action of any kind or nature
whatsoever ("Claims") against all or any of the Agent, the Lenders or any of the
Agent's or the Lenders' directors, officers, employees, agents, attorneys,
financial advisors, accountants, legal representatives, successors and assigns
(the Agent, the Lenders and their directors, officers, employees, agents,
attorneys, financial advisors, accountants, legal representatives, successors
and assigns are jointly and severally referred to as the "Lender Group"), that
directly or indirectly arise out of or are based upon or in any manner connected
with any "Prior Event" (as defined below), and each Credit Party, on behalf of
itself and any Person claiming by, through or under such Credit Party, hereby
releases the Lender Group from any liability whatsoever should any Claims
nonetheless exist. As used herein the term "Prior Event" means any transaction,
event, circumstances, action, failure to act or occurrence of any sort or type,
whether known or unknown, which occurred, existed, was taken, permitted or begun
prior to the execution of this First Amendment and occurred, existed, was taken,
permitted or begun in accordance with, pursuant to or by virtue of any terms of
this First Amendment, the transactions referred to herein, any Loan Document or
oral or written agreement relating to any of the foregoing, including without
limitation any approval or acceptance given or denied.

         5. Representations and Warranties. By its execution hereof, the
Borrower hereby certifies on behalf of itself and the other Credit Parties that
each of the representations and warranties set forth in the Credit Agreement and
the other Loan Documents is true and correct as of the date hereof as if fully
set forth herein, and that as of the date hereof no Default or Event of Default
(other than Events of Default occurring as a result of the occurrence of the
Acknowledged Defaults) has occurred and is continuing. Additionally, the
Borrower represents and warrants that since April 13, 2000, no event which has
had, or could reasonably be expected to have, a Material Adverse Effect has
occurred, except as previously disclosed in writing to the Agent.

         6. Conditions. The effectiveness of this First Amendment shall be
conditioned upon the following:

         (a) The following documents shall have been duly authorized and
executed by the parties thereto, shall be in full force and effect and no
default shall exist thereunder, and the Borrower shall have delivered original
counterparts thereof the Agent:

                  (i)      this First Amendment, duly executed and delivered by
                           the Credit Parties, the Agent and the Lenders
                           constituting Required Lenders; and

                  (ii)     such other documents, certificates and instruments as
                           the Agent reasonably requests.

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         (b) The Borrower shall have paid all outstanding fees and expenses, to
the extent that the Borrower has received an invoice for such fees and expenses,
through the date hereof of Stroock & Stroock & Lavan LLP ("SSL"), Policano &
Manzo LLP, and Kennedy, Covington, Lobdell & Hickman, L.L.P. and shall, in
addition, have paid SSL a retainer of one hundred thousand ($100,0000) dollars
to be applied against any unpaid fees and expenses from and after the date
hereof through the Waiver Maturity Date.

         7. Waiver of Subrogation Rights. Notwithstanding anything to the
contrary in the Subsidiary Guaranty or any other Loan Document, each Credit
Party hereby irrevocably waives any claims or other rights which it may now have
or hereafter acquire against the Borrower or any other obligor that arise from
the existence, payment, performance or enforcement of such Guarantor's
obligations under the Subsidiary Guaranty or any other Loan Document, including
any right of subrogation, reimbursement, exoneration or indemnification, any
right to participate in any claim or remedy of Agent or any Lender against the
Borrower or any other obligor or any collateral which Agent or any Lender now
has or hereafter acquires, whether or not such claim, remedy or right arises in
equity, or under contract, statute or common law, including, but not limited to,
the right to take or receive from the Borrower or any other obligor, directly or
indirectly, in cash or other property or by setoff or any manner, payment or
security on account of such claim or other rights. If any amount shall be paid
to any Guarantor in violation of the preceding sentence, such amount shall be
deemed to have been paid to such Guarantor for the benefit of, and held in trust
for, the Lenders and shall forthwith be paid to the Agent on behalf of the
Lenders to be credited and applied against the Guaranteed Obligations, whether
matured or unmatured.

         8. Governing Law. THE WAIVER AGREEMENT, AS AMENDED HEREIN, AND EACH
OTHER LOAN DOCUMENT, UNLESS OTHERWISE EXPRESSLY SET FORTH THEREIN, SHALL BE
GOVERNED BY, CONSTRUED AND ENFORCED IN ACCORDANCE WITH THE LAWS OF THE STATE OF
NORTH CAROLINA, WITHOUT REFERENCE TO THE CONFLICTS OR CHOICE OF LAW PRINCIPLES
THEREOF.

         9.       Miscellaneous.

         a. Reversal of Payments. To the extent the Borrower makes a payment or
payments to the Agent for the ratable benefit of Lenders pursuant to the Waiver
Agreement, as amended herein, the Notes or any other Loan Document which
payments or proceeds or any part thereof are subsequently invalidated, declared
to be fraudulent or preferential, set aside and/or required to be repaid to a
trustee, receiver or any other party under any bankruptcy law, state or federal
law, common law or equitable cause, then, to the extent of such payment or
proceeds repaid, the Obligations or part thereof intended to be satisfied shall
be revived and continued in full force and effect as if such payment or proceeds
had not been received by the Agent.

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         b.       Arbitration.

                              (i) Binding Arbitration. Upon demand of any party,
                  whether made before or after institution of any judicial
                  proceeding, any dispute, claim or controversy arising out of,
                  connected with or relating to the Waiver Agreement, as amended
                  herein, the Notes or any other Loan Documents ("Disputes"),
                  between or among parties to this First Amendment, the Notes or
                  any other Loan Document shall be resolved by binding
                  arbitration as provided herein. Institution of a judicial
                  proceeding by a party does not waive the right of that party
                  to demand arbitration hereunder. Disputes may include, without
                  limitation, tort claims, counterclaims, claims brought as
                  class actions, claims arising from Loan Documents executed in
                  the future, or claims concerning any aspect of the past,
                  present or future relationships arising out or connected with
                  the Loan Documents. Arbitration shall be conducted under and
                  governed by the Commercial Financial Disputes Arbitration
                  Rules (the "Arbitration Rules") of the American Arbitration
                  Association (the "AAA") and Title 9 of the U.S. Code. All
                  arbitration hearings shall be conducted in Charlotte, North
                  Carolina. The expedited procedures set forth in Rule 51, et
                  seq., of the Arbitration Rules shall be applicable to claims
                  of less than $1,000,000. All applicable statutes of limitation
                  shall apply to any Dispute. A judgment upon the award may be
                  entered in any court having jurisdiction. The panel from which
                  all arbitrators are selected shall be comprised of licensed
                  attorneys. The single arbitrator selected for expedited
                  procedure shall be a retired judge from the highest court of
                  general jurisdiction, state or federal, of the state where the
                  hearing will be conducted. The arbitrators shall be appointed
                  as provided in the Arbitration Rules.

                              (ii) Preservation of Certain Remedies.
                  Notwithstanding the preceding binding arbitration provisions,
                  the Agent and the Lenders preserve, without diminution,
                  certain remedies that the Agent and the Lenders may employ or
                  exercise freely, either alone, in conjunction with or during a
                  Dispute. The Agent and the Lenders shall have and hereby
                  reserve the right to proceed in any court of proper
                  jurisdiction or by self help to exercise or prosecute the
                  following remedies: (A) all rights to foreclose against any
                  real or personal property or other security by exercising a
                  power of sale granted in the Loan Documents or under
                  applicable law or by judicial foreclosure and sale, (B) all
                  rights of self help including peaceful occupation of property
                  and collection of rents, set off, and peaceful possession of
                  property and (C) obtaining provisions or ancillary remedies
                  including injunctive relief, sequestration, garnishment,
                  attachment, appointment of receiver and in filing an
                  involuntary bankruptcy proceeding. Preservation of these
                  remedies does not limit the power of any arbitrator to grant
                  similar remedies that may be requested by a party in a
                  Dispute.

         c. Waiver of Jury Trial. TO THE EXTENT PERMITTED BY APPLICABLE LAW, THE
AGENT, EACH LENDER AND THE BORROWER HEREBY IRREVOCABLY WAIVE THEIR RESPECTIVE
RIGHTS TO A JURY TRIAL WITH RESPECT TO ANY



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ACTION, CLAIM OR OTHER PROCEEDING ARISING OUT OF ANY DISPUTE IN CONNECTION WITH
THE WAIVER AGREEMENT, AS AMENDED HEREIN, THE NOTES OR THE OTHER LOAN DOCUMENTS,
ANY RIGHTS OR OBLIGATIONS HEREUNDER OR THEREUNDER, OR THE PERFORMANCE OF SUCH
RIGHTS AND OBLIGATIONS.

         d. Survival of Terms of Agreement. The waivers, agreements, covenants,
representations and warranties of each Credit Party in the Waiver Agreement, as
amended herein, shall survive the Waiver Maturity Date.

         10. Counterparts. This First Amendment may be executed in separate
counterparts, each of which when executed and delivered is an original but all
of which taken together constitute one and the same instrument.

                            [Signature pages follow]

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         IN WITNESS WHEREOF, the parties hereto have caused this First Amendment
to be duly executed as of the date and year first above written.

                                    BORROWER:

                                    RURAL/METRO CORPORATION, a Delaware
                                    corporation

                                    By: /s/ Dean Hoffman
                                       _________________________________________
                                    Name: Dean Hoffman
                                         _______________________________________
                                    Title: Vice President
                                          ______________________________________


                            [Signature pages follow]
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                                    LENDERS:

                                    FIRST UNION NATIONAL BANK,
                                    as Agent and Lender

                                    By: /s/ Ron R. Ferguson
                                       _________________________________________
                                    Name: Ron R. Ferguson
                                         _______________________________________
                                    Title: Senior Vice President
                                          ______________________________________




                            [Signature pages follow]

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                                     FLEET BANK, N.A., as Lender

                                    By: /s/ Vincent Pitts
                                       _________________________________________
                                    Name: Vincent Pitts
                                         _______________________________________
                                    Title: Vice President
                                          ______________________________________




                            [Signature pages follow]

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                                    BANK ONE, NA, as Lender

                                    By: /s/ BONNIE D. WILSON
                                       _________________________________________

                                    Name: Bonnie D. Wilson
                                         _______________________________________

                                    Title:  Vice President
                                          ______________________________________




                            [Signature pages follow]

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                                    ABN AMRO BANK N.V., as Lender

                                    By: /s/ WILLIAM J. FITZGERALD
                                       _________________________________________

                                    Name: William J. Fitzgerald
                                         _______________________________________

                                    Title: Senior Vice President
                                          ______________________________________



                                    By: /s/ WILLIAM J. TERESKY, JR.
                                       _________________________________________

                                    Name: William J. Teresky, Jr.
                                         _______________________________________

                                    Title: Vice President
                                          ______________________________________




                            [Signature pages follow]

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                                    WELLS FARGO BANK, as Lender


                                    By: /s/ ART BROKX
                                       _________________________________________

                                    Name:  Art Brokx
                                         _______________________________________

                                    Title: Vice President
                                          ______________________________________




                            [Signature pages follow]

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                                    GENERAL ELECTRIC CAPITAL
                                    CORPORATION, as Lender


                                    By:    /s/ Thomas E. Johnstone
                                    Name:      Thomas E. Johnstone
                                    Title:  Duly Authorized Signatory




                            [Signature pages follow]

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                                     BANK OF AMERICA NATIONAL TRUST AND
                                     SAVINGS ASSOCIATION, as Lender


                                    By:    /s/ Kurt A. Huisman
                                    Name:      Kurt A. Huisman
                                    Title:  Vice President




                            [Signature pages follow]

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                                     PARIBAS, as Lender


                                    By:      /s/ William A. Wexler
                                    Name:        William A. Wexler
                                    Title:    Director


                                    By:      /s/ Edward V. Canale
                                    Name:        Edward V. Canale
                                    Title:    Managing Director


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By execution hereof, the undersigned Subsidiary Guarantors hereby acknowledge
and agree to the terms hereof, including, without limitation, Section 7 of this
First Amendment; hereby reaffirm their respective obligations under the
Subsidiary Guaranty and the Intercompany Subordination Agreement; acknowledge
that the Guaranty Obligations with respect to the Subsidiary Guaranty include
the obligations under this First Amendment; acknowledge that the Senior Debt as
defined in and with respect to the Intercompany Subordination Agreement include
the obligations under this First Amendment; and hereby agree that the terms of
the Subsidiary Guaranty shall remain in full force and effect notwithstanding
any event or condition which has occurred.

ACCEPTED AND AGREED TO AS OF APRIL 13, 2000.
AID AMBULANCE AT VIGO COUNTY, INC., an Indiana corporation, AMBULANCE TRANSPORT
SYSTEMS, INC., a New Jersey corporation, AMERICAN LIMOUSINE SERVICE, INC., an
Ohio corporation, ARROW AMBULANCE, INC., an Idaho corporation, BEACON
TRANSPORTATION, INC., a New York corporation, COASTAL EMS, INC., a Georgia
corporation, CORNING AMBULANCE SERVICE INC., a New York corporation, DONLOCK,
LTD., a Pennsylvania corporation, E.M.S. VENTURES, INC., a Georgia corporation,
EMS VENTURES OF SOUTH CAROLINA, INC., a South Carolina corporation, EASTERN
AMBULANCE SERVICE, INC., a Nebraska corporation, EASTERN PARAMEDICS, INC., a
Delaware corporation, GOLD CROSS AMBULANCE SERVICES, INC., a Delaware
corporation, GOLD CROSS AMBULANCE SERVICE OF PA., INC., an Ohio corporation,
KEEFE & KEEFE, INC., a New York corporation, KEEFE & KEEFE AMBULETTE, LTD., a
New York corporation, LASALLE AMBULANCE INC., a New York corporation, MEDI-CAB
OF GEORGIA, INC., a Delaware corporation, MEDICAL EMERGENCY DEVICES AND SERVICES
(MEDS), INC., an Arizona corporation, MEDICAL TRANSPORTATION SERVICES, INC., a
South Dakota corporation, MEDSTAR EMERGENCY MEDICAL SERVICES, INC., a Delaware
corporation, MERCURY AMBULANCE SERVICE, INC., a Kentucky corporation, METRO CARE
CORP., an Ohio corporation, MO-RO-KO, INC., an Arizona corporation, MULTI CAB
INC., a New Jersey corporation, MULTI-CARE INTERNATIONAL, INC., a New Jersey
corporation, MULTI-CARE MEDICAL CAR SERVICE, INC., a New Jersey corporation,
MULTI-HEALTH CORP., a Florida corporation, MYERS AMBULANCE SERVICE, INC., an
Indiana corporation, NATIONAL AMBULANCE & OXYGEN SERVICE, INC., a New York
corporation, NORTH MISS. AMBULANCE SERVICE, INC., a Mississippi corporation,
PROFESSIONAL MEDICAL SERVICES, INC., an Arkansas corporation, RISC AMERICA
ALABAMA FIRE SAFETY SERVICES, INC., a Delaware corporation, RMFD OF NEW JERSEY,
INC., a Delaware corporation, R/M MANAGEMENT CO., INC., an Arizona corporation,
R/M OF MISSISSIPPI, INC., a Delaware corporation, R/M OF TENNESSEE G.P., INC., a
Delaware corporation, R/M OF TENNESSEE L.P., INC., a Delaware corporation, R/M
OF TEXAS G.P., INC., a Delaware corporation, R/M PARTNERS, INC., a Delaware
corporation, RMC CORPORATE CENTER, L.L.C., an Arizona limited liability company,
By: RURAL/METRO CORPORATION, an Arizona corporation, Its Member, RURAL/METRO
ARGENTINA, L.L.C., an Arizona limited liability company, By: RURAL/METRO
INTERNATIONAL, INC., a Delaware corporation, Its Member, RURAL/METRO BRASIL,
L.L.C., an Arizona limited liability company, By: RURAL/METRO INTERNATIONAL,
INC., a Delaware corporation, Its Member, RURAL/METRO CANADIAN HOLDINGS, INC., a
Delaware corporation, RURAL/METRO COMMUNICATIONS SERVICES, INC., a Delaware
corporation, RURAL/METRO CORPORATION, an Arizona corporation, RURAL/METRO
CORPORATION OF FLORIDA, a Florida corporation, RURAL/METRO CORPORATION OF
TENNESSEE, a Tennessee corporation, RURAL/METRO FIRE DEPT., INC., an Arizona
corporation, RURAL/METRO HOSPITAL SERVICES, INC., a Delaware corporation


                                    By: /s/ DEAN HOFFMAN
                                        ----------------------------------------
                                    Name: Dean Hoffman
                                          --------------------------------------
                                    Title: Vice President
                                           -------------------------------------


                                       19
<PAGE>   20
RURAL/METRO INTERNATIONAL, INC., a Delaware corporation, RURAL/METRO LOGISTICS,
INC., a Delaware corporation, RURAL/METRO MID-ATLANTIC, INC., a Delaware
corporation, RURAL/METRO MID-SOUTH, L.P., a Delaware limited partnership, By:
R/M OF TENNESSEE G.P., INC., a Delaware corporation, Its General Partner,
RURAL/METRO OF ALABAMA, INC., a Delaware corporation, RURAL/METRO OF ARGENTINA,
INC., a Delaware corporation, RURAL/METRO OF ARKANSAS, INC., a Delaware
corporation, RURAL/METRO OF ARLINGTON, INC., a Delaware corporation, RURAL/METRO
OF BRASIL, INC., a Delaware corporation, RURAL/METRO OF CALIFORNIA, INC., a
Delaware corporation, RURAL/METRO OF CENTRAL ALABAMA, INC., a Delaware
corporation, RURAL/METRO OF CENTRAL COLORADO, INC., a Delaware corporation,
RURAL/METRO OF CENTRAL OHIO, INC., a Delaware corporation, RURAL/METRO OF
COLORADO, a Delaware corporation, RURAL/METRO OF GEORGIA, INC., a Delaware
corporation, RURAL/METRO OF GREATER SEATTLE, INC., a Washington corporation,
RURAL/METRO OF INDIANA, INC., a Delaware corporation, RURAL/METRO OF INDIANA,
L.P., a Delaware limited partnership, By: THE AID AMBULANCE COMPANY, INC., a
Delaware corporation, Its General Partner, RURAL/METRO OF INDIANA II, L.P., a
Delaware limited partnership, By: THE AID AMBULANCE COMPANY, INC., a Delaware
corporation, Its General Partner, RURAL/METRO OF KENTUCKY, INC., a Delaware
corporation, RURAL/METRO OF MISSISSIPPI, INC., a Delaware corporation,
RURAL/METRO OF NEBRASKA, INC., a Delaware corporation, RURAL/METRO OF NEVADA,
INC., a Delaware corporation, RURAL/METRO OF NEW YORK, INC., a Delaware
corporation, RURAL/METRO OF NORTH FLORIDA, INC., a Florida corporation,
RURAL/METRO OF NORTH TEXAS, L.P., By: R/M OF TEXAS G.P., INC., a Delaware
corporation, Its General Partner, RURAL/METRO OF NORTHERN OHIO, INC., a Delaware
corporation, RURAL/METRO OF OHIO, INC., a Delaware corporation, RURAL/METRO OF
OREGON, INC., a Delaware corporation, RURAL/METRO OF ROCHESTER, INC., a New York
corporation, RURAL/METRO OF SAN DIEGO, INC., a California corporation,
RURAL/METRO OF SOUTH CAROLINA, INC., a Delaware corporation, RURAL/METRO OF
SOUTH DAKOTA, INC., a Delaware corporation, RURAL/METRO OF SOUTHERN OHIO, INC.,
an Ohio corporation, RURAL/METRO OF TENNESSEE, L.P., a Delaware limited
partnership, By: R/M OF TENNESSEE G.P., INC., a Delaware corporation, Its
General Partner, RURAL/METRO OF TEXAS, INC., a Delaware corporation, RURAL/METRO
OF TEXAS, L.P., a Delaware limited partnership, By: R/M OF TEXAS G.P., INC., a
Delaware corporation, Its General Partner, RURAL/METRO PROTECTION SERVICES,
INC., an Arizona corporation, RURAL/METRO TEXAS HOLDINGS, INC., a Delaware
corporation, SW GENERAL, INC., an Arizona corporation, SIOUX FALLS AMBULANCE,
INC., a South Dakota corporation, SOUTH GEORGIA EMERGENCY MEDICAL SERVICES,
INC., a Georgia corporation, SOUTHWEST AMBULANCE AND RESCUE OF ARIZONA, INC., an
Arizona corporation, SOUTHWEST AMBULANCE OF CASA GRANDE, INC., an Arizona
corporation, SOUTHWEST AMBULANCE OF TUCSON, INC., an Arizona corporation,
SOUTHWEST GENERAL SERVICES, INC., an Arizona corporation, THE AID AMBULANCE
COMPANY, INC., a Delaware corporation, THE AID COMPANY, INC., an Indiana
corporation, TOWNS AMBULANCE SERVICE, INC., a New York corporation, VALLEY FIRE
SERVICE, INC., a Delaware corporation, W & W LEASING COMPANY, INC., an Arizona
corporation

                                    By: /s/ Dean Hoffman
                                        ----------------------------------------
                                    Name: Dean Hoffman
                                          --------------------------------------
                                    Title: Vice President
                                           -------------------------------------


                                       20
<PAGE>   21
                                    EXHIBIT A


                       FORM OF CASH FLOW PROJECTION REPORT

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