<PAGE>

                                                                   EXHIBIT 10.67


                           SECOND AMENDMENT OF LEASE

     THIS SECOND AMENDMENT OF LEASE (this "Amendment") is hereby entered into as
of the 18/th/ day of November, 1999 by Bishop 108 Associates Limited Partnership
(the "Landlord") and Lifeline Systems, Inc. (the "Tenant").

                                  WITNESSETH:

     WHEREAS, reference is hereby made to that certain Lease, dated as of
November 17, 1997, as amended by that certain First Amendment of Lease dated as
of June 30, 1998 (as so amended, the "Lease") entered into by and between the
Landlord and the Tenant; and

     WHEREAS, any capitalized term used and not defined herein shall have the
meaning set forth in the Lease; and

     WHEREAS, the Landlord and the Tenant have agreed that the Tenant shall pay
the Cost Difference by paying to the Landlord a lump sum amount and by paying
increased Rent, all as set forth below; and

     WHEREAS, the Landlord and the Tenant desire to amend the Lease to
incorporate said agreement as set forth below

     NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, and notwithstanding anything
contained in the Lease to the contrary, the Landlord and Tenant hereby agree as
follows:

     1.  Simultaneously with the execution of this Amendment by the Tenant, the
Tenant shall pay Four Hundred Twenty Thousand, Seven Hundred Twenty-Seven and
50/100 Dollars ($420,727.50) (the "First Lump Sum Payment") to the Landlord. The
First Lump Sum Payment consists of: (a) a one-time payment to the Landlord in
the amount of Three Hundred Seventy-Five Thousand Dollars ($375,000.00); and (b)
an additional payment of Base Rent in the amount of Forty-Five Thousand, Seven
Hundred Twenty-Seven and 50/100 Dollars ($45,727.50) (the "Retroactive Increase
in Base Rent"). The Retroactive Increase in Base Rent is for the period from the
Term Commencement Date (which is November 1, 1998) through and including
November 30, 1999 and was calculated by multiplying Fifty Cents (.50) per annum
per rentable square foot of space in the Leased Premises (which the parties
irrevocably agreed in the Lease is 84,420 square feet of rentable floor space).
The failure of the Tenant to pay the First Lump Sum Payment to the Landlord
within three (3) business days after the execution of this Amendment by the
Tenant, Landlord and Lender (hereafter defined) shall be deemed to be a default
by the Tenant in the payment of Rent due under the Lease.

                                       1
<PAGE>

     2.  On or before October 1, 2000, the Tenant shall pay to the Landlord
Forty Thousand and 00/100 Dollars ($40,000.00) (the "Second Lump Sum Payment").
The failure of the Tenant to pay the Second Lump Sum Payment to the Landlord on
or before October 1, 2000 shall be deemed to be a default by the Tenant in the
payment of Rent due under the Lease.

     3.  The definition of "Original Lease Term" set forth in Section 1.1 of the
Lease is hereby deleted in its entirety and the following definition is hereby
substituted therefor: "Original Lease Term: Fifteen (15) Lease Years commencing
on the Term Commencement Date and ending on the last day of the fifteenth Lease
Year."

     4.  Section 3.2.1 of the Lease is hereby deleted in its entirety and the
following section is substituted therefor:

        3.2.1 Base Rent   Tenant shall pay Base Rent as follows:
              ---------

              (a) Lease Years 1-5:  For the period commencing on the Term
                  ---------------
        Commencement Date and continuing through and including the last day of
        the fifth (5th) Lease Year, the Base Rent shall be at the annual rate of
        Eight Hundred Thirteen Thousand, Nine Hundred Ninety Dollars
        ($813,990.00) and shall be payable in equal monthly installments, in
        advance, each in the amount of Sixty-Seven Thousand, Eight Hundred
        Thirty-Two and 50/100 Dollars ($67,832.50). Said annual rate of Base
        Rent was calculated by multiplying Nine and 50/100 Dollars ($9.50) by
        the number of square feet of rentable space in the Leased Premises
        (which the parties irrevocably agree is 84,420 square feet of rentable
        floor space) and adding Twelve Thousand Dollars ($12,000); and

              (b) Lease Years 6-10:  For the period commencing on the first day
                  ----------------
        of the sixth (6/th/) Lease Year and continuing through and including the
        last day of the tenth (10/th/) Lease Year, the Base Rent shall be at the
        annual rate of Nine Hundred Nineteen Thousand, Five Hundred Fifteen and
        00/100 Dollars ($919,515.00) and shall be payable in equal monthly
        installments, in advance, each in the amount of Seventy-Six Thousand,
        Six Hundred Twenty-Six and 25/100 Dollars ($76,626.25) Dollars
        ($76,626.25). Said annual rate of Base Rent was calculated by
        multiplying Ten and 75/100 Dollars ($10.75) by the number of square feet
        of rentable space in the Leased Premises (which the parties irrevocably
        agree is 84,420 square feet of rentable floor space) and adding Twelve
        Thousand Dollars ($12,000); and

              (c) Lease Years 11-15:  For the remainder of the Original Lease
                  -----------------
        Term, the Base Rent shall be at the annual rate of One Million, Eighty-
        Eight Thousand, Three Hundred Fifty-Five and 00/100 Dollars
        ($1,088,355.00) and shall be payable in equal monthly installments, in
        advance, each in the amount of Ninety Thousand,

                                       2
<PAGE>

        Six Hundred Ninety-Six and 25/100 Dollars ($90,696.25) Dollars. Said
        annual rate of Base Rent was calculated by multiplying Twelve and 75/100
        Dollars ($12.75) by the number of square feet of rentable space in the
        Leased Premises (which the parties irrevocably agree is 84,420 square
        feet of rentable floor space) and adding Twelve Thousand Dollars
        ($12,000).

     5.  The first two sentences of Section 3.2A are hereby deleted in their
entirety and the following sentences are substituted therefor:

        Tenant shall have the right to seek, at the Tenant's expense, a "TIF"
     agreement with the Town of Framingham (the "Town") to reduce the real
     estate taxes assessed against the Property. After January 1, 2000, Landlord
     shall cooperate with Tenant in Tenant's efforts to obtain such a TIF
     agreement provided that Landlord shall not be subjected to any liability
     for the payment of any costs or expenses in connection therewith, and
     Tenant shall indemnify and save harmless Landlord from any such costs and
     expenses.

     6.  The second sentence in Section 3.3(1) is hereby deleted in its entirety
and the following sentence is substituted therefor: "The "Base Amount" shall be
the amount of the real estate taxes imposed, assessed or levied upon the
Property by the Town for the year beginning on July 1, 1999 and ending on June
30, 2000 without regard to any reduction in the real estate taxes levied on the
Property by the Town pursuant to any TIF agreement between the Tenant and the
Town."

     7.  Landlord and Tenant agree that this Second Amendment represents a full
and final settlement of all disputes regarding the Cost Difference.

     8.  Promptly after the execution and delivery hereof by all parties,
Landlord and Tenant shall execute and deliver, and Tenant may cause to be
recorded at its expense, an amendment to the existing Notice of Lease on record
in Middlesex South Registry of Deeds and the Middlesex South Registry District
of the Land Court reflecting the change in the definition of the Original Lease
Term.

     9.  The Lease, as amended by this Amendment, is hereby ratified and
confirmed and is in full force and effect.

     10. Notwithstanding anything contained herein to the contrary, this Second
Amendment shall not be deemed to be effective unless and until the holder of the
mortgage on the Property, CIBC Inc. ("Lender") consents to this Second Amendment
by signing below. Landlord represents that Lender is the only holder of a
mortgage on the Property and that no other consent or approval is required in
order for this Lease Amendment to be binding upon Landlord.

                                       3
<PAGE>

     11. This Amendment may be executed in any number of counterparts with the
same effect as if all parties hereto had signed the same instrument. All
counterparts shall be construed together and shall constitute one original
instrument.

     In Witness Whereof, the parties hereto have executed this Amendment under
seal as of the date first written above.

LANDLORD:                                TENANT:
BISHOP 108 ASSOCIATES LIMITED            LIFELINE SYSTEMS, INC.
PARTNERSHIP
By:  BISHOP 108 CORPORATION
     the sole General Partner

     By: /s/ Donald A. Levine            By: /s/ Dennis M. Hurley
        ---------------------               ---------------------
        Donald A. Levine, President         Dennis M. Hurley
                                            Vice President of Finance

Lender joins in this Agreement for the purpose of consenting to this Second
Amendment to Lease, and confirming that, for the purposes of that certain
Subordination, Non-Disturbance and Attornment Agreement dated as of July 27,
1998 recorded in Middlesex County Registry of Deeds as Instrument No. 1352 on
July 27, 1998 and filed with the Middlesex County Registry District of the Land
Court as Document No.  1075583, the "Lease" as defined therein shall mean the
Lease as modified by this Second Amendment of Lease.


LENDER:
CIBC INC.


By: /s/ Ryan P Sparks
   ------------------
   Name: Ryan P. Sparks
   Title: Assistant Asset Manager

                                       4