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                                                                    EXHIBIT 10.1


                      FOURTH AMENDMENT TO LOAN INSTRUMENTS


         This FOURTH AMENDMENT TO LOAN INSTRUMENTS (this "FOURTH AMENDMENT"),
dated as of August __, 2000, is between SECURITY ASSOCIATES INTERNATIONAL, INC.,
a Delaware corporation ("BORROWER") and FINOVA CAPITAL CORPORATION, a Delaware
corporation ("FINOVA"), in its individual capacity and as agent for the
financial institutions from time to time parties to the Loan Agreement (this and
all other capitalized terms not otherwise defined herein shall have the meanings
ascribed thereto in Section 2 below).

                                    RECITALS

         A. Borrower, State Street Bank and Trust Company ("STATE STREET"), and
FINOVA entered into a Second Amended and Restated Loan Agreement dated as of
September 30, 1999 (the "ORIGINAL LOAN AGREEMENT"), which was amended by a First
Amendment to Loan Instruments dated as of February 11, 2000 (the "FIRST
AMENDMENT") among Borrower, Citizens Bank of Massachusetts ("CITIZENS BANK"), as
successor in interest to State Street, and FINOVA, a Second Amendment to Loan
Instruments dated as of March 10, 2000 (the "SECOND AMENDMENT") among Borrower,
Citizens Bank and FINOVA and a Third Amendment to Loan Instruments dated as of
May 16, 2000 (the "THIRD AMENDMENT") among Borrower, Citizens Bank and FINOVA.
The Original Loan Agreement, as amended by the First Amendment, the Second
Amendment and the Third Amendment is referred to herein as the "LOAN AGREEMENT."
Pursuant to the Loan Agreement, Lenders have agreed to make loans and other
financial accommodations to Borrower.

         B. Citizens Bank has assigned its interest in the Loan Agreement to
FINOVA pursuant to an Assignment and Acceptance Agreement of even date herewith
between Citizens Bank and FINOVA.

         C. Borrower has requested that the Loan Agreement be further amended in
certain respects and that certain Events of Default be waived. Subject to the
terms and conditions of this Fourth Amendment, Lenders are willing to agree to
the requests of Borrower.

         NOW, THEREFORE, in consideration of the mutual agreements contained
herein, and subject to the terms and conditions hereof, Borrower and Lenders
agree as follows:

         1. INCORPORATION OF RECITALS. The Recitals set forth above are
incorporated herein, are acknowledged by Borrower to be true and correct and are
made a part hereof.

         2. DEFINITIONS. All capitalized terms used but not elsewhere defined
herein shall have the respective meanings ascribed to such terms in the Loan
Agreement, as amended by this Fourth Amendment.

         3. AMENDMENTS TO THE LOAN AGREEMENT. The Loan Agreement is amended as
set forth below:

               3.1 SUBSECTION 1.1 - DELETED DEFINITIONS. Section 1.1 is amended
            by deleting the definitions "Acquisition Portion" and "Advance."

               3.2 SUBSECTION 1.1 - ADDITIONAL DEFINITIONS. Section 1.1 is
            amended by adding the following definitions in the appropriate
            alphabetical order:


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                  "Fourth Amendment: the Fourth Amendment to Loan Instruments
               dated as of August __, 2000 among Borrower and Lenders.

                  "King/Monital Proposed Acquisition: a series of acquisitions
               pursuant to which KC Acquisition Corp. proposes to acquire
               substantially all of the assets of Monital Signal Corporation,
               and subsequent to such acquisition, Borrower proposes to cause a
               wholly-owned subsidiary of Borrower to merge with KC Acquisition
               Corp., with such subsidiary as the surviving entity."

               3.3 SECTION 2.1. Section 2.1 is deleted in its entirety and the
            following is substituted therefor:

                   "2.1.1 AGGREGATE LOAN AMOUNT. The Loan shall consist of a
               term credit facility made available by Lenders to Borrower in the
               maximum aggregate amount of $17,500,000. As of the date of the
               Fourth Amendment, (i) $300,000 of the Capital Expenditure
               Portion, (ii) $1,800,000 of the SAFE Attrition Guaranty Portion
               and (iii) $2,000,000 of the SAFE Debt Portion remain available to
               be disbursed on or before December 31, 2000 pursuant to the terms
               hereof.

                   "2.1.2 INTENTIONALLY OMITTED.

                   "2.1.3 INTENTIONALLY OMITTED.

                   "2.1.4 USE OF PROCEEDS. The proceeds of the Initial Portion
               were used (i) to pay transaction costs, (ii) to reimburse
               Borrower for certain Capital Expenditures permitted hereunder and
               (iii) for working capital. The proceeds of the Capital
               Expenditure Portion have been and shall continue to be used to
               reimburse Borrower for certain Capital Expenditures permitted
               hereunder. The proceeds of the SAFE Attrition Guaranty Portion
               have been and shall continue to be used to repay certain
               obligations to SAFE (i) in connection with the reprogramming of
               account telephone lines (the "Telephone Reprogramming
               Obligations") and (ii) arising under the SAFE Attrition Guaranty.
               If SAFE has delivered a certificate to Borrower stating that all
               amounts owing from Borrower to SAFE pursuant to the Telephone
               Reprogramming Obligations and the SAFE Attrition Guaranty have
               been satisfied, any amounts remaining under the SAFE Attrition
               Guaranty Portion may be used for Capital Expenditures permitted
               hereunder. The proceeds of the SAFE Debt Portion shall be used to
               repay the SAFE Debt or, in the event that Borrower is not
               obligated to repay the SAFE Debt pursuant to the terms of the
               SAFE Debt Instruments, for Capital Expenditures permitted
               hereunder.

                   "2.1.5 NOTES. The Loan shall be evidenced by the Notes.

                   "2.1.6 REBORROWING. Borrower shall not be entitled to
               reborrow any portion of the Loan which is repaid or prepaid.

                   "2.1.7 FUNDING PROCEDURES. Agent shall give each Lender
               prompt notice by telephone or facsimile transmission of a Notice
               of Borrowing that is received by it. Each applicable Lender shall
               make available to Agent, no later than 1:00 p.m. Eastern Time on
               the applicable Funding Date set forth in the Notice of Borrowing,
               for deposit into such account


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               as Borrower may direct, its Pro Rata Share of such Additional
               Portion Advance in immediately available funds in Dollars,
               provided that all of the conditions set forth in Sections 4.1 and
               4.4 have been satisfied with respect to a Additional Portion
               Advance requested in such Notice of Borrowing.

                   "Unless Agent receives contrary written notice prior to any
               such Additional Portion Advance, it is entitled to assume that
               each applicable Lender will make available its Pro Rata Share of
               the Additional Portion Advance and in reliance upon that
               assumption, but without any obligation to do so, may advance such
               Pro Rata Share on behalf of the applicable Lender, without the
               necessity of giving daily notice to such Lender of the receipt of
               a Notice of Borrowing. If the applicable amount is not in fact
               made available to Agent by such Lender, Agent shall be entitled
               to recover such amount on demand from such Lender together with
               interest thereon, for each day from such Funding Date until the
               date such amount is paid to Agent, at the Base Rate. If such
               Lender pays such amount to Agent, then such amount shall
               constitute such Lender's Pro Rata Share of the applicable
               Additional Portion Advance. If such Lender does not pay such
               corresponding amount forthwith upon Agent's demand therefor,
               Agent shall promptly notify the Borrower and the Borrower shall
               immediately pay such corresponding amount to Agent together with
               interest thereon, for each day from such Funding Date until the
               date such amount is paid to Agent, at the rate payable under this
               Loan Agreement for the Base Rate Portion.

                   "Nothing in this subsection 2.1.7 shall be deemed to relieve
               any Lender from its obligation to fulfill its Commitments
               hereunder or to prejudice any rights that Borrower may have
               against any Lender as a result of any default by such Lender
               hereunder. It is understood and agreed that no Lender shall be
               responsible for any default by any other Lender in that other
               Lender's obligation to make an Additional Portion Advance
               requested hereunder nor shall the Commitment of any Lender to
               make the particular type of Additional Portion Advance requested
               be increased or decreased as a result of a default by any other
               Lender in that other Lender's obligation to make an Additional
               Portion Advance requested hereunder."

               3.4 SUBSECTION 2.6.2. Subsection 2.6.2 is deleted in its entirety
            and the following is substituted therefor:


                   "2.6.2 NON-UTILIZATION FEE. Borrower shall pay to Agent, for
               the benefit of Lenders, for each month through December 31, 2000,
               a fee in the amount of one-half of one percent (.50%) per annum
               (the "NON-UTILIZATION FEE") on the remainder of (i) $17,500,000
               minus (ii) the Principal Balance as of the last day of such
               month. The Non-Utilization Fee shall be payable monthly in
               arrears on the first Business Day of each month."

               3.5 SECTION 2.7.1 (a). Subsection 2.7.1(a) is deleted in its
            entirety and the following is substituted therefor:

                   "2.7.1(a) PREPAYMENT PREMIUM. Except as provided in
               subsection 2.7.3, concurrently with any voluntary prepayment of
               all or any part of the Principal Balance, Borrower shall pay to
               Lenders a prepayment premium (the "PREPAYMENT PREMIUM") equal to
               a percentage of the amount of the Principal Balance prepaid,
               determined in accordance with the following schedule:


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<TABLE>
<CAPTION>
                                                                             Percentage of Principal
                           Period of Prepayment                              Balance Prepaid
                           --------------------                              ---------------
<S>                                                                          <C>
                           First Loan Year                                   2.0%
                           October 1, 2000 through December 31, 2000         1.0%
                           Thereafter                                        0.0%"
</TABLE>

               3.6 SECTION 4.3. Section 4.3 is deleted in its entirety and the
            following is substituted therefor:

                   "4.3 INTENTIONALLY OMITTED."

               3.7 SECTION 7.3. Section 7.3 is deleted in its entirety and the
            following is substituted therefor:

                  "7.3 MERGER AND ACQUISITION. Consolidate with or merge with or
               into any Person, or acquire directly or indirectly all or
               substantially all of the capital stock, equity interests,
               membership interests or Property of any Person, or otherwise
               enter into any agreement for, or consummate or cause to be
               consummated any Acquisition, including without limitation the
               King/Monital Proposed Acquisition, except that any Subsidiary of
               Borrower may merge with and into Borrower."

               3.8 SCHEDULE I. Schedule I is deleted in its entirety and
            replacement Schedule I, attached hereto, is substituted therefor.

         4. CONDITIONS TO EFFECTIVENESS. The effectiveness of this Fourth
Amendment shall be subject to the satisfaction of all of the following
conditions in a manner, form and substance satisfactory to Lenders:


               4.1 DELIVERY OF DOCUMENTS. The following shall have been
            delivered to Agent, each duly authorized and executed and each in
            form and substance satisfactory to Lenders:


                   (a) this Fourth Amendment;

                   (b) an Assignment and Acceptance Agreement dated on or before
                       the date of this Fourth Amendment executed by Citizens
                       Bank and FINOVA;

                   (c) a copy, certified by the corporate secretary of Borrower,
                       of resolutions adopted by the Board of Directors of
                       Borrower authorizing the execution of this Fourth
                       Amendment;

                   (d) such other instruments, documents, certificates,
                       consents, waivers and opinions as Lenders reasonably may
                       request.

               4.2 PERFORMANCE; NO DEFAULT. Each Obligor shall have performed
            and complied with all agreements and conditions contained in the
            Loan Instruments to be performed by or complied with by it, and no
            Event of Default or Incipient Default shall exist, other than as
            waived in Paragraph 6 hereof.


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               4.3 MATERIAL ADVERSE CHANGE. No event shall have occurred since
            December 31, 1999 which has had or could have a Material Adverse
            Effect.


The date on which all of the conditions set forth in this Paragraph 4 have been
satisfied is referred to herein as the "Effective Date."

         5. REFERENCES. From and after the Effective Date, all terms used in the
Loan Instruments which are defined in the Loan Agreement shall be deemed to
refer to such terms as amended by this Fourth Amendment.


         6. WAIVER OF EVENTS OF DEFAULT UNDER SECTIONS 7.21 AND 7.22. From and
after the Effective Date, Lenders shall be deemed to have waived their rights to
pursue their remedies as a result of Borrower's failure to comply with Sections
7.21 and 7.22 of the Loan Agreement for the quarter ending June 30, 2000. The
foregoing waiver shall not be deemed a waiver of any other Event of Default
which may have occurred under the Loan Agreement, and except as specifically set
forth above, Lenders reserve and preserve all of their rights and remedies under
the Loan Agreement and the other Loan Instruments.

         7. AMENDMENT FEE. In consideration of Lenders' entry into this Fourth
Amendment, Borrower agrees to pay to Lenders a non-refundable amendment fee of
$112,500, which shall be deemed to be fully earned and payable upon the date
hereof and which shall be charged against the Principal Balance of Borrower as
of the date of the Fourth Amendment.

         8. KING/MONITAL PROPOSED ACQUISITION. Borrower acknowledges and agrees
that (i) neither Agent nor any Lender has consented to, nor shall the execution
and delivery of this Fourth Amendment be deemed to be a consent by Agent or any
Lender to the entry into any agreement for, or the consummation of, the
King/Monital Proposed Acquisition, (ii) neither Agent nor any Lender has agreed
or committed to provide, nor shall the execution and delivery of this Fourth
Amendment be deemed to be an agreement or commitment by Agent or any Lender to
provide, financing in connection with the King/Monital Proposed Acquisition and
(iii) neither Agent nor any Lender has received the necessary due diligence
information with respect to the King/Monital Proposed Acquisition to enable such
Person to decide whether or not to consent to the entry into any agreement for,
or the consummation of, the King/Monital Proposed Acquisition.

         9. REPRESENTATIONS AND WARRANTIES. Borrower hereby confirms to Agent
and Lenders that the representations and warranties set forth in the Loan
Instruments, as amended by this Fourth Amendment, are true and correct in all
material respects as of the date hereof, and shall be deemed to be remade as of
the date hereof. Borrower represents and warrants to Agent and Lenders that (i)
Borrower has full power and authority to execute and deliver this Fourth
Amendment and to perform its obligations hereunder, (ii) upon the execution and
delivery hereof, this Fourth Amendment will be valid, binding and enforceable
upon Borrower in accordance with its terms, (iii) the execution and delivery of
this Fourth Amendment does not and will not contravene, conflict with, violate
or constitute a default under (A) its articles of incorporation or by-laws or
(B) any applicable law, rule, regulation, judgment, decree or order or any
agreement, indenture or instrument to which Borrower is a party or is bound or
which is binding upon or applicable to all or any portion of Borrower's Property
and (iv) as of the date hereof no Incipient Default or Event of Default exists,
other than as waived in Paragraph 6 hereof.

        10. COSTS AND EXPENSES. Borrower agrees to reimburse Agent for all fees
and expenses incurred in the preparation, negotiation and execution of this
Fourth Amendment and the consummation of the transactions contemplated hereby,
including, without limitation, the fees and expenses of counsel for Agent.



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         11. NO FURTHER AMENDMENTS; RATIFICATION OF LIABILITY. Except as amended
hereby, the Loan Agreement and each of the other Loan Instruments shall remain
in full force and effect in accordance with its respective terms. Borrower
hereby ratifies and confirms its liabilities, obligations and agreements under
the Loan Agreement and the other Loan Instruments, all as amended by this Fourth
Amendment, and the Liens created thereby, and acknowledges that (i) it has no
defenses, claims or set-offs to the enforcement by Agent and Lenders of such
liabilities, obligations and agreements, (ii) Agent and Lenders have fully
performed all obligations to Borrower which any such Person may have had or has
on and as of the date hereof and (iii) other than as specifically set forth
herein, neither Agent nor any Lender waives, diminishes or limits any term or
condition contained in the Loan Agreement or the other Loan Instruments. Agent
and Lenders' agreement to the terms of this Fourth Amendment or any other
amendment of the Loan Agreement shall not be deemed to establish or create a
custom or course of dealing among Agent, Lenders and Borrower. The Loan
Instruments, as amended by this Fourth Amendment, contain the entire agreement
among Agent, Lenders and Borrower with respect to the transactions contemplated
hereby.

         12. COUNTERPARTS. This Fourth Amendment may be executed in one or more
counterparts, each of which shall be deemed an original, and all of which, when
taken together, shall constitute one and the same instrument.

         13. FURTHER ASSURANCES. Borrower covenants and agrees that it will at
any time and from time to time do, execute, acknowledge and deliver, or will
cause to be done, executed, acknowledged and delivered, all such further acts,
documents and instruments as reasonably may be required by Agent and Lenders in
order to effectuate fully the intent of this Fourth Amendment.

         14. SEVERABILITY. If any term or provision of this Fourth Amendment or
the application thereof to any party or circumstance shall be held to be
invalid, illegal or unenforceable in any respect by a court of competent
jurisdiction, the validity, legality and enforceability of the remaining terms
and provisions of this Fourth Amendment shall not in any way be affected or
impaired thereby, and the affected term or provision shall be modified to the
minimum extent permitted by law so as most fully to achieve the intention of
this Fourth Amendment.

         15. CAPTIONS. The captions in this Fourth Amendment are inserted for
convenience of reference only and in no way define, describe or limit the scope
or intent of this Fourth Amendment or any of the provisions hereof.


                [remainder of this page intentionally left blank]



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         IN WITNESS WHEREOF, this Fourth Amendment has been executed and
delivered by each of the parties hereto by a duly authorized officer of each
such party on the date first set forth above.

                                         SECURITY ASSOCIATES INTERNATIONAL, INC.


                                         By:
                                            ------------------------------------
                                            James S. Brannen
                                            President

                                         FINOVA CAPITAL CORPORATION, in its
                                         individual capacity as a Lender and as
                                         Agent for all Lenders


                                         By:
                                            ------------------------------------
                                            Andrew J. Pluta
                                            Vice President


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                             REPLACEMENT SCHEDULE I
                TO THE SECOND AMENDED AND RESTATED LOAN AGREEMENT

                                   COMMITMENTS


            LENDER                                   COMMITMENT
            ------                                   ----------

            FINOVA Capital Corporation               $17,500,000




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