LIFELINE SYSTEMS, INC. 2000 EMPLOYEE STOCK PURCHASE PLAN

Exhibit 10.1

LIFELINE SYSTEMS, INC.

2000 EMPLOYEE STOCK PURCHASE PLAN

The purpose of this Plan is to provide eligible employees of Lifeline Systems, Inc. (the “Company”) and certain of its subsidiaries with opportunities to purchase shares of the Company’s common stock, $.02 par value (the “Common Stock”). Two hundred thousand (200,000) shares of Common Stock in the aggregate have been approved for this purpose.

1. Administration. The Plan will be administered by the Company’s Board of Directors (the “Board”) or by a Committee appointed by the Board (the “Committee”). The Board or the Committee has authority to make rules and regulations for the administration of the Plan and its interpretation and decisions with regard thereto shall be final and conclusive.

2. Eligibility. Participation in the Plan will neither be permitted nor denied contrary to the requirements of Section 423 of the Internal Revenue Code of 1986, as amended (the “Code”), and regulations promulgated thereunder. All employees of the Company, including Directors who are employees, and all employees of any subsidiary of the Company (as defined in Section 424(f) of the Code) designated by the Board or the Committee from time to time (a “Designated Subsidiary”), are eligible to participate in any one or more of the offerings of options (as defined in Section 9) to purchase Common Stock under the Plan provided that:

(a) they are regularly employed by the Company or a Designated Subsidiary for more than 20 hours a week and for more than five months in a calendar year; and

(b) they have been employed by the Company or a Designated Subsidiary for at least six months prior to enrolling in the Plan; and

(c) they are employees of the Company or a Designated Subsidiary on the first day of the applicable Plan Period (as defined below).

No employee may be granted an option hereunder if such employee, immediately after the option is granted, owns 5% or more of the total combined voting power or value of the stock of the Company or any subsidiary. For purposes of the preceding sentence, the attribution rules of Section 424(d) of the Code shall apply in determining the stock ownership of an employee, and all stock which the employee has a contractual right to purchase shall be treated as stock owned by the employee.

3. Offerings. The Company will make ten offerings (“Offerings”) to employees to purchase stock under this Plan.

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If any of the above dates is not a business date, the offering shall commence or terminate, as applicable, on the first business day thereafter. The date of the commencement of each offering is referred to herein as an “Offering Commencement Date” and the date of termination of each Offering is referred to herein as an “Offering Termination Date.” Each Offering period is referred to herein as a “Plan Period,” during which payroll deductions will be made and held for the purchase of Common Stock at the end of the Plan Period.

4. Participation. An employee eligible on the Offering Commencement Date of any Offering may participate in such offering by completing and forwarding a payroll deduction authorization form to the office of Human Resources of the Company at least seven but not more than 30 days prior to the applicable Offering Commencement Date. The form will authorize a regular payroll deduction from the Compensation received by the employee during the Plan Period. Unless an employee files a new form or withdraws from the Plan, his deductions and purchases will continue at the same rate for future Offerings under the Plan as long as the Plan remains in effect. The term “Compensation” means the amount of money reportable on the employee’s Federal Income Tax Withholding Statement and includes any amounts deferred under a salary reduction agreement under an IRS Code Section 401(k) plan or Section 125 plan. Compensation excludes allowances and reimbursements for expenses such as relocation allowances for travel expenses and executive medical reimbursements, income or gains on the exercise of Company stock options or stock appreciation rights, and similar items, whether or not shown on the employee’s Federal Income Tax Withholding Statement.

5. Deductions. The Company will maintain payroll deduction accounts for all participating employees. With respect to any Offering made under this Plan, an employee may authorize a payroll deduction in any dollar amount up to a maximum of 15% of the Compensation he or she receives during the Plan Period or such shorter period during which deductions from payroll are made. Payroll deductions may be at the rate of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15% of Compensation with any change in compensation during the Plan Period to result in an automatic corresponding change in the dollar amount withheld.

No employee may be granted an Option (as defined in Section 9) which permits his rights to purchase Common Stock under this Plan and any other stock purchase plan of the Company and its subsidiaries, to accrue at a rate which exceeds $25,000 of the fair market value of such Common Stock (determined at the Offering Commencement Date of the Plan Period) for each calendar year in which the Option is outstanding at any time.

6. Deduction Changes. An employee may not increase or decrease his or her payroll deduction during a Plan Period.

7. Interest. Interest will not be paid on any employee accounts, except as otherwise provided herein.

8. Withdrawal of Funds. An employee may at any time prior to the close of business on the last business day in a Plan Period and for any reason permanently draw out the balance accumulated in the employee’s account and thereby withdraw from participation in an Offering by providing written notice of withdrawal to the office of Human Resources of the Company. Partial withdrawals are not permitted. The employee may not begin participation again during the remainder of the Plan Period. The employee may participate in any subsequent Offering in accordance with terms and conditions established by the Board or the Committee, except that employees who are also directors or officers of the Company within the meaning of Section 16 of the Securities Exchange Act of 1934 (the “Exchange Act”) and the rules promulgated there under may not participate again for a period of at least six months as provided in Rule 16b-3(d)(2)(i) or any successor provision.

9. Purchase of Shares. On the Offering Commencement Date of each Plan Period, the Company will grant to each eligible employee who is then a participant in the Plan an option (“Option”) to purchase on the last business day of such Plan Period (the “Exercise Date”), at the option Price hereinafter provided for, such number of whole shares of Common Stock of the Company reserved for the purposes of the Plan as does not exceed the number of shares determined by (i) multiplying an amount equal to 150% of the employee’s annualized base pay as of the Offering Commencement Date by the percentage of it which he or she has elected to have withheld (but not in excess of 15%), (ii) dividing such product by 85% of the market value of a share of Common Stock as of the offering Commencement Date, and (iii) multiplying such quotient by 1.25, but in no event more than 600 shares. The market value of the Common Stock shall be determined as provided in the following paragraph. An employee’s annualized base pay shall be

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determined as follows: (i) in the case of a full-time employee normally paid on an hourly rate, by multiplying his or her normal hourly rate by 2080; (ii) in the case of a part-time employee normally paid on an hourly rate, by multiplying his or her normal hourly rate by the product of 52 times the number of hours in his or her normal work week; (iii) in the case of an employee normally paid at a weekly rate, by multiplying his or her normal weekly rate by 52; (iv) in the case of an employee normally paid at a bi-weekly rate, by multiplying his or her normal biweekly rate by 26; and (v) in the case of an employee normally paid at a semi-monthly rate, by multiplying his or her normal semi-monthly rate by 24, and (vi) in the case of an employee normally paid at a monthly rate, by multiplying his or her normal monthly rate by 12.

The purchase price for each share purchased will be 85% of the closing price of the Common Stock on (i) the first business day of such Plan Period or (ii) the Exercise Date, whichever closing price shall be less. Such closing price shall be (a) the closing price on any national securities exchange on which the Common Stock is listed, (b) the closing price of the Common Stock on the Nasdaq National Market or (c) the average of the closing bid and asked prices in the over-the-counter-market, whichever is applicable, as published in The Wall Street Journal. If no sales of Common Stock were made on such a day, the price of the Common Stock for purposes of clauses (a) and (b) above shall be the reported price for the next preceding day on which sales were made.

Each employee who continues to be a participant in the Plan on the Exercise Date shall be deemed to have exercised his Option at the Option Price on such date and shall be deemed to have purchased from the Company the number of full shares of Common Stock reserved for the purpose of the Plan that his accumulated payroll deductions on such date will pay for pursuant to the formula set forth above (but not in excess of the maximum number determined in the manner set forth above).

Any balance remaining in an employee’s payroll deduction account at the end of a Plan Period will be automatically refunded to the employee.

10. Issuance of Certificates. Certificates representing shares of Common Stock purchased under the Plan may be issued only in the name of the employee, in the name of the employee and another person of legal age as joint tenants with rights of survivorship, or (in the Company’s sole discretion) in the street name of a brokerage firm, bank or other nominee holder designated by the employee.

11. Rights on Retirement, Death or Termination of Employment. In the event of a participating employee’s termination of employment prior to the last business day of a Plan Period, no payroll deduction shall be taken from any pay due and owing to an employee and the balance in the employee’s account shall be paid to the employee or, in the event of the employee’s death, (a) to a beneficiary previously designated in a revocable notice signed by the employee (with any spousal consent required under state law) or (b) in the absence of such a designated beneficiary, to the executor or administrator of the employee’s estate or (c) if no such executor or administrator has been appointed to the knowledge of the Company, to such other person(s) as the Company may, in its discretion, designate. If, prior to the last business day of the Plan Period, the Designated Subsidiary by which an employee is employed shall cease to be a subsidiary of the Company, or if the employee is transferred to a subsidiary of the Company that is not a Designated Subsidiary, the employee shall be deemed to have terminated employment for the purposes of this Plan.

12. Optionees Not Stockholders. Neither the granting of an Option to an employee nor the deductions from his pay shall constitute such employee a stockholder of the shares of Common Stock covered by an Option under this Plan until such shares have been purchased by and issued to him.

13. Rights Not Transferable. Rights under this Plan are not transferable by a participating employee other than by will or the laws of descent and distribution, and are exercisable during the employee’s lifetime only by the employee.

14. Application of Funds. All funds received or held by the Company under this Plan may be combined with other corporate funds and may be used for any corporate purpose.

15. Adjustment in Case of Changes Affecting Common Stock. In the event of a subdivision of outstanding shares of Common Stock, or the payment of a dividend in Common Stock, the number of shares approved for this Plan, and the share limitation set forth in Section 9, shall be increased proportionately, and such other adjustment shall be made as

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may be deemed equitable by the Board or the Committee. In the event of any other change affecting the Common Stock, such adjustment shall be made as may be deemed equitable by the Board or the Committee to give proper effect to such event.

16. Merger. If the Company shall at any time merge with another corporation and the Company is the surviving entity, the holder of each Option then outstanding will thereafter be entitled to receive at the next Offering Termination Date upon the exercise of such Option for each share as to which such Option shall be exercised the securities or property which a holder of one share of the Common Stock was entitled to upon and at the time of such merger, and the Board of Directors shall take such steps in connection with such merger as the Board of Directors shall deem necessary to assure that the provisions of Paragraph 15 shall thereafter be applicable, as nearly as reasonably may be, in relation to the said securities or property as to which such holder of such Option might thereafter be entitled to receive thereunder. In the event of a merger in which the Company is not the surviving entity, or of a sale of all or substantially all of the assets of the Company, the Plan shall terminate, and all payroll deductions credited to participants’ accounts shall be returned to them, with simple interest computed at the 90-day Treasury Bill rate as of the applicable Offering Commencement Date; provided, however, that the Board of Directors may, in the event of such merger or sale, accelerate the Offering Termination Date of the Offering then in effect and permit participants to purchase shares under the Plan at such accelerated Offering Termination Date.

17. Change of Control. Notwithstanding any other provision of the Plan and except as otherwise provided in the relevant option agreement, in the event of a “Change in Control of the Company” (as defined below), the Board of Directors may accelerate the Offering Termination Date of the Offering then in effect and permit participants to purchase shares under the Plan at such accelerated Offering Termination Date. For purposes of the Plan a “Change in Control of the Company” shall occur or be deemed to have occurred on if (i) any “person,” as such term is used in Sections 13(d) and 14(d) of the Exchange Act (other than the Company, any trustee or other fiduciary holding securities under an employee benefit plan of the Company, or any corporation owned directly or indirectly by the stockholders of the Company in substantially the same proportion as their ownership of stock of the Company), is or becomes the “beneficial owner” (as defined in Rule 13d-3 under the Exchange Act), directly or indirectly, of securities of the Company representing 30% or more of the combined voting power of the Company’s then outstanding securities; (ii) during any period of two consecutive years ending during the term of the Plan (not including any period prior to the adoption of the Plan), individuals who at the beginning of such period constitute the Board of Directors of the Company, and any new director (other than a director designated by a person who has entered into an agreement with the Company to effect any transaction described in clause W, (iii) or (iv) of this Section 17) whose election by the Board of Directors or nomination for election by the Company’s stockholders was approved by a vote of at least two-thirds of the directors then still in office who were either directors at the beginning of the period or whose election or whose nomination for election was previously so approved (collectively, the “Disinterested Directors”), cease for any reason to constitute a majority of the Board of Directors; (iii) the stockholders of the Company approve a merger or consolidation of the Company with any other corporation, other than (A) a merger or consolidation which would result in the voting securities of the Company outstanding immediately prior thereto continuing to represent (either by remaining outstanding or by being converted into voting securities of the surviving entity) more than 50% of the combined voting power of the voting securities of the Company or such surviving entity outstanding immediately after such merger or consolidation or (B) a merger or consolidation effected to implement a recapitalization of the Company (or similar transaction) in which no “Person” (as hereinabove defined) acquires more than 30% of the combined voting power of the Company’s then outstanding securities or (C) a merger or consolidation which has been approved by a majority of the Disinterested Directors; or (iv) the stockholders of the Company approve a plan of complete liquidation of the Company or an agreement for the sale or disposition by the Company of all or substantially all of the Company’s assets which, in either case, has not previously been approved by a majority of the Disinterested Directors. Notwithstanding the foregoing, the Board of Directors of the Company may, in its sole discretion, by a resolution adopted by two-thirds of the Disinterested Directors prior to the occurrence of any of the events otherwise constituting a Change in Control of the Company, declare that such event will not constitute a Change in Control of the Company for the purposes of the Plan. If such resolution is adopted, such event shall not constitute a Change in Control of the Company for any purpose of the Plan.

18. Amendment of the Plan. The Board may at any time, and from time to time, amend this Plan in any respect, except that (a) if the approval of any such amendment by the shareholders of the Company is required by Section 423 of the Code or by Rule 16b-3 under the Exchange Act, such amendment shall not be effected without such approval, and

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(b) in no event may any amendment be made which would cause the Plan to fail to comply with Section 16 of the Exchange Act and the rules promulgated thereunder, as in effect from time to time, or Section 423 of the Code.

19. Insufficient Shares. In the event that the total number of shares of Common Stock specified in elections to be purchased under any Offering plus the number of shares purchased under previous Offerings under this Plan exceeds the maximum number of shares issuable under this Plan, the Board or the Committee will allot the shares then available on a pro rata basis. The balance of the payroll deductions credited to the account of each participating employee shall be returned to him or her with simple interest computed upon such balance at the 90-day U.S. Treasury Bill rate as of the applicable Offering Commencement Date.

20. Termination of the Plan. This Plan may be terminated at any time by the Board. Upon termination of this Plan all amounts in the accounts of participating employees shall be promptly refunded.

21. Governmental Regulations. The Company’s obligation to sell and deliver Common Stock under this Plan is subject to listing on a national stock exchange or quotation on the NASDAQ National Market and the approval of all governmental authorities required in connection with the authorization, issuance or sale of such stock.

The Plan shall be governed by Massachusetts law except to the extent that such law is preempted by federal law.

The Plan is intended to comply with the provisions of Rule 16b-3 promulgated under the Securities Exchange Act of 1934. Any provision inconsistent with such Rule shall to that extent be inoperative and shall not affect the validity of the Plan.

22. Issuance of Shares. Shares may be issued upon exercise of an Option from authorized but unissued Common Stock, from shares held in the treasury of the Company, or from any other proper source.

23. Notification upon Sale of Shares. Each employee agrees, by entering the Plan, to promptly give the company notice of any disposition of shares purchased under the Plan where such disposition occurs within two years after the date of grant of the Option pursuant to which such shares were purchased.

24. Effective Date and Approval of Shareholders. The Plan shall take effect on February 2, 2000, subject to approval by the shareholders of the Company as required by Rule 16b-3 under the Exchange Act and by Section 423 of the Code, which approval must occur within twelve months of the adoption of the Plan by the Board.

Adopted by the Board of Directors on February 2, 2000

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Exhibit A

LIFELINE SYSTEMS, INC.

AMENDMENT TO THE 2000 EMPLOYEE STOCK PURCHASE PLAN

The 2000 Employee Stock Purchase Plan (the “Plan”) of Lifeline Systems, Inc. (the “Company”) is hereby amended as follows:

“6. Deduction Changes and Discontinuation. An employee may not increase or decrease his or her payroll deduction during a Plan Period; provided, however, an employee may discontinue his or her payroll deduction for all remaining payroll deduction dates in a Plan Period by providing written notice to the office of Human Resources of the Company at least fourteen days prior to the next payroll deduction date if and only if the employee’s aggregate payroll deductions for such Plan Period have exceeded the amount which would be necessary to purchase all of the shares of Common Stock for which an Option was granted under Section 9 of the Plan for such Plan Period (subject to any reduction necessary to comply with the limit set forth in the second paragraph of Section 5) at a purchase price per share of 85% of the closing price of the Common Stock on the first business day of such Plan Period.”

Approved by the Board of Directors on March 24, 2004.

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