NATUS MEDICAL, INC.

Exhibit 10.28

NATUS MEDICAL, INC.

JAMES B. HAWKINS EMPLOYMENT AGREEMENT

This Agreement is entered into as of April 12, 2004, (the “Effective Date”) by and between Natus Medical, Inc. (the “Company”), and James B. Hawkins (“Executive”).

1. Duties and Scope of Employment.

(a) Positions and Duties. As of the Effective Date, Executive shall be an employee of the Company, and starting on April 19, 2004, shall serve as President and Chief Executive Officer of the Company. Executive will render such business and professional services in the performance of his duties, consistent with Executive’s position within the Company, as shall reasonably be assigned to him by the Company’s Board of Directors (“Board”). The period of Executive’s employment under this Agreement is referred to herein as the “Employment Term.”

(b) Obligations. During the Employment Term, Executive will perform his duties faithfully and to the best of his ability and will devote his full business efforts and time to the Company. For the duration of the Employment Term, Executive agrees not to actively engage in any other employment, occupation or consulting activity for any direct or indirect remuneration without the prior approval of the Board.

2. At-Will Employment. The parties agree that Executive’s employment with the Company will be “at-will” employment and may be terminated at any time with or without cause or notice. Executive understands and agrees that neither his job performance nor promotions, commendations, bonuses or the like from the Company give rise to or in any way serve as the basis for modification, amendment, or extension, by implication or otherwise, of his employment with the Company.

3. Compensation.

(a) Base Salary. During the Employment Term, the Company will pay Executive an annual salary of three-hundred-and-ten thousand dollars ($310,000.00) as compensation for his services (the “Base Salary”). The Base Salary will be paid periodically in accordance with the Company’s normal payroll practices and be subject to the usual, required withholding. Executive’s salary will be subject to review and adjustments will be made based upon the Company’s normal performance review practices.

(b) Performance Bonus. Executive shall be eligible to receive an annual bonus of a maximum of one-hundred thousand dollars ($100,000.00) less applicable withholding taxes, upon achievement of performance objectives to be determined by the Board in its sole discretion, which such objectives shall be established within ninety (90) days of the Effective Date.

(c) Stock Options. Stock Options. Executive shall be eligible to receive options to purchase seven-hundred-thousand (700,000) shares of Common stock of the Company, pursuant to and governed by the terms of the Natus 2000 Supplemental Stock Option Plan, with an exercise price at the closing market price on the day prior to the Effective Date. Vesting begins after your first six (6) months of employment and is retroactive to your start date. Stock vests at 1/48^th per month. Options must be exercised within ten (10) years of date of hire. Notwithstanding any other provision of the Agreement, under no circumstances shall Executive have any right to exercise stock options before Executive has completed one-hundred-eighty-days of employment.

4. Employee Benefits. During the Employment Term, Executive will be entitled to participate in the employee benefit plans currently and hereafter maintained by the Company of general applicability to other senior executives of the Company, including, without limitation, the Company’s group medical, dental, vision, disability, life insurance, and flexible-spending account plans. The Company reserves the right to cancel or change the benefit plans and programs it offers to its employees at any time.

5. Paid Time Off (“PTO”). Executive is entitled to receive PTO pursuant to Natus’ standard benefit policy currently and hereafter maintained by the Company, and as may be cancelled or changed from time to time.

6. Expenses. The Company will reimburse Executive for reasonable travel, entertainment or other expenses incurred by Executive in the furtherance of or in connection with the performance of Executive’s duties hereunder, in accordance with the Company’s expense reimbursement policy as in effect from time to time.

7. Severance.

(a) Involuntary Termination. If, after more than one hundred eighty (180) days from commencement of employment, Executive’s employment with the Company terminates other than for “Cause” (as defined herein), death or disability, and Executive signs and does not revoke a standard release of claims with the Company, then, subject to Section 11, Executive shall be entitled to (i) receive continuing payments of severance pay (less applicable withholding taxes) at a rate equal to his Base Salary rate, as then in effect, for a period of twelve (12) months from the date of such termination, to be paid periodically in accordance with the Company’s normal payroll policies; (ii) the immediate vesting and exercisability of 100% of the shares subject to all of Executive’s stock options to purchase Company Common Stock (whether currently outstanding or granted in following the Effective Date) outstanding on the date of such termination (the “Stock Options”) and (iii) continued payment by the Company of the group health continuation coverage premiums for Executive and Executive’s eligible dependents under Title X of the Consolidated Budget Reconciliation Act of 1985, as amended (“COBRA”) as in effect through the lesser of (x) twelve (12) months from the effective date of such termination, (y) the date upon which Executive and Executive’s eligible dependents become covered under similar plans, or (z) the date Executive no longer constitutes a “Qualified Beneficiary” (as such term is defined in Section 4980B(g) of the Internal Revenue Code of 1986, as amended (the “Code”)); provided, however, that Executive will be solely responsible for electing such coverage within the required time periods.

(b) Voluntary Termination; Termination for Cause. If Executive’s employment with the Company terminates voluntarily by Executive (other than as described in subsection (c) below) or for Cause by the Company or due to Executive’s death or disability, or involuntarily for any reason within one hundred and eighty (180) days of commencement of employment, then (i) all vesting of Stock Options will immediately cease, (ii) all payments of compensation by the Company to Executive hereunder will terminate immediately (except as to amounts already earned), and (iii) Executive will only be eligible for severance benefits, if any, in accordance with the Company’s established policies as then in effect.

(c) Change of Control Benefits. If within twelve (12) months following a “Change of Control” (as defined below) (i) Executive terminates Executive’s employment with the Company for Good Reason, or (ii) the Company or the successor corporation terminates Executive’s employment with the Company for other than Cause, death or disability, then Executive shall be entitled to the benefits provided for in subsection (a). Executive shall only be permitted to receive the benefits provided for in subsection (a) once and shall not be permitted to claim such benefits under both subsection (a) and (c) such that Executive would receive the benefits pursuant to subsection (a) twice.

8. Limitation on Payments. In the event that the severance and other benefits provided for in this Agreement or otherwise payable to the Executive (i) constitute “parachute payments” within the meaning of Section 280G of the Code and (ii) but for this Section 8, would be subject to the excise tax imposed by Section 4999 of the Code, then the Executive’s severance benefits under Section 4(a)(i) shall be either:

delivered in full, or

delivered as to such lesser extent which would result in no portion of such severance benefits being subject to excise tax under Section 4999 of the Code,

whichever of the foregoing amounts, taking into account the applicable federal, state and local income taxes and the excise tax imposed by Section 4999, results in the receipt by Executive on an after-tax basis, of the greatest

amount of severance benefits, notwithstanding that all or some portion of such severance benefits may be taxable under Section 4999 of the Code. Unless the Company and Executive otherwise agree in writing, any determination required under this Section 8 shall be made in writing by the Company’s independent public accountants immediately prior to Change of Control (the “Accountants”), whose determination shall be conclusive and binding upon Executive and the Company for all purposes. For purposes of making the calculations required by this Section 8, the Accountants may make reasonable assumptions and approximations concerning applicable taxes and may rely on reasonable, good faith interpretations concerning the application of Sections 280G and 4999 of the Code. The Company and Executive shall furnish to the Accountants such information and documents as the Accountants may reasonably request in order to make a determination under this Section. The Company shall bear all costs the Accountants may reasonably incur in connection with any calculations contemplated by this Section 8.

9. Definitions.

(a) Cause. For purposes of this Agreement, “Cause” shall mean (i) commission of any act of dishonesty, fraud, misrepresentation or other act of moral turpitude by Executive, (ii) Executive’s conviction of a felony, (iii) a willful act by Executive which constitutes disloyalty or gross misconduct injurious to the Company, (iv) misrepresentation or concealment by Executive of any fact for the purpose of securing or maintaining this Agreement, or (v) continued violations by Executive of Executive’s employment duties which are willful on Executive’s part after Executive has been given written demand for performance from the Board which specifically sets forth the factual basis for the Board’s belief that Executive has not substantially performed Executive’s duties.

(b) Change of Control. For purposes of this Agreement, “Change of Control” of the Company is defined as:

(i) any “person” (as such term is used in Sections 13(d) and 14(d) of the Securities Exchange Act of 1934, as amended) is or becomes the “beneficial owner” (as defined in Rule 13d-3 under said Act), directly or indirectly, of securities of the Company representing 50% or more of the total voting power represented by the Company’s then outstanding voting securities; or

(ii) the date of the consummation of a merger or consolidation of the Company with any other corporation that has been approved by the stockholders of the Company, other than 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 forty percent (40%) of the total voting power represented by the voting securities of the Company or such surviving entity outstanding immediately after such merger or consolidation, or the stockholders of the Company approve a plan of complete liquidation of the Company; or

(iii) the date of the consummation of the sale or disposition by the Company of all or substantially all the Company’s assets.

(c) Good Reason. For purposes of this Agreement, “Good Reason” shall mean without the Executive’s express written consent shall mean (i) the significant reduction of the Executive’s duties or responsibilities relative to Executive’s duties or responsibilities in effect immediately prior to such reduction; provided, however, that a reduction in duties or responsibilities solely by virtue of the Company being acquired and made part of a larger entity (as, for example, when the Chief Financial Officer remains as such following a Change of Control and is not made the Chief Financial Officer of the acquiring corporation) shall not constitute “Good Reason;” (ii) a reduction by the Company in Executive’s annual Base Salary as in effect immediately prior to such reduction; (iii) a material reduction by the Company in the kind or level of employee benefits to which Executive is entitled immediately prior to such reduction with the result that Executive’s overall benefits package is significantly reduced; (iv) the relocation of Executive to a facility or a location more than 35 miles from Executive’s then present location, without Executive’s express written consent; or (v) the failure of the Company to obtain the assumption of this Agreement by any successors contemplated in Section 12.

10. Confidential Information; Representation. Executive agrees to enter into the Company’s standard Confidential Information and Invention Assignment Agreement (the “Confidential Information Agreement”) upon commencing employment hereunder. Executive represents and warrants that all personal background information provided by him, or to be provided during the term of his employment, in response to background questions asked by the Company pertaining to Executive’s employment, is true and accurate, and does not and will not contain any material omissions, nor shall it omit any material information. Executive further represents and warrants that he has not committed any act as described in section 9(a)(i), (ii) or (iv) hereof.

11. Conditional Nature of Severance Payments.

(a) Noncompete. Executive acknowledges that the nature of the Company’s business is such that if Executive were to become employed by, or substantially involved in, the business of a competitor of the Company following the termination of Executive’s employment with the Company, it would be very difficult for Executive not to rely on or use the Company’s trade secrets and confidential information. Thus, to avoid the inevitable disclosure of the Company’s trade secrets and confidential information, Executive agrees and acknowledges that Executive’s right to receive the severance payments set forth in Section 7 (to the extent Executive is otherwise entitled to such payments) shall be conditioned upon Executive not directly or indirectly engaging in (whether as an employee, consultant, agent, proprietor, principal, partner, stockholder, corporate officer, director or otherwise), nor having any ownership interest in or participating in the financing, operation, management or control of, any person, firm, corporation or business that competes with Company or is a customer of the Company. Upon any breach of this section, all severance payments pursuant to this Agreement shall immediately cease.

(b) Non-Solicitation. Until the date eighteen (18) months after the termination of Executive’s employment with the Company for any reason, Executive agrees not, either directly or indirectly, to solicit, induce, attempt to hire, recruit, encourage, take away, hire any employee of the Company or cause an employee to leave his or her employment either for Executive or for any other entity or person. Additionally, Executive acknowledges that Executive’s right to receive the severance payments set forth in Section 7 (to the extent Executive is otherwise entitled to such payments) are contingent upon Executive complying with this Section 10(b) and upon any breach of this section all severance payments pursuant to this Agreement shall immediately cease.

(c) Understanding of Covenants. Executive represents that Executive (i) is familiar with the foregoing covenants not to compete and not to solicit, and (ii) is fully aware of Executive’s obligations hereunder, including, without limitation, the reasonableness of the length of time, scope and geographic coverage of these covenants.

12. Assignment. This Agreement will be binding upon and inure to the benefit of (a) the heirs, executors and legal representatives of Executive upon Executive’s death and (b) any successor of the Company. Any such successor of the Company will be deemed substituted for the Company under the terms of this Agreement for all purposes. For this purpose, “successor” means any person, firm, corporation or other business entity which at any time, whether by purchase, merger or otherwise, directly or indirectly acquires all or substantially all of the assets or business of the Company. None of the rights of Executive to receive any form of compensation payable pursuant to this Agreement may be assigned or transferred except by will or the laws of descent and distribution. Any other attempted assignment, transfer, conveyance or other disposition of Executive’s right to compensation or other benefits will be null and void.

13. Notices. All notices, requests, demands and other communications called for hereunder shall be in writing and shall be deemed given (i) on the date of delivery if delivered personally, (ii) one (1) day after being sent by a well established commercial overnight service, or (iii) four (4) days after being mailed by registered or certified mail, return receipt requested, prepaid and addressed to the parties or their successors at the following addresses, or at such other addresses as the parties may later designate in writing:

If to the Company:

Natus Medical, Inc.

1501 Industrial Road

San Carlos, CA 94070

Attn: Mark E. Foster, General Counsel

If to Executive:

at the last residential address known by the Company.

14. Severability. In the event that any provision hereof becomes or is declared by a court of competent jurisdiction to be illegal, unenforceable or void, this Agreement will continue in full force and effect without said provision.

15. Arbitration.

(a) General. In consideration of Executive’s service to the Company, its promise to arbitrate all employment related disputes and Executive’s receipt of the compensation, pay raises and other benefits paid to Executive by the Company, at present and in the future, Executive agrees that any and all controversies, claims, or disputes with anyone (including the Company and any employee, officer, director, shareholder or benefit plan of the Company in their capacity as such or otherwise) arising out of, relating to, or resulting from Executive’s service to the Company under this Agreement or otherwise or the termination of Executive’s service with the Company, including any breach of this Agreement, shall be subject to binding arbitration under the Arbitration Rules set forth in California Code of Civil Procedure Section 1280 through 1294.2, including Section 1283.05 (the “Rules”) and pursuant to California law. Disputes which Executive agrees to arbitrate, and thereby agrees to waive any right to a trial by jury, include any statutory claims under state or federal law, including, but not limited to, claims under Title VII of the Civil Rights Act of 1964, the Americans with Disabilities Act of 1990, the Age Discrimination in Employment Act of 1967, the Older Workers Benefit Protection Act, the California Fair Employment and Housing Act, the California Labor Code, claims of harassment, discrimination or wrongful termination and any statutory claims. Executive further understands that this Agreement to arbitrate also applies to any disputes that the Company may have with Executive.

(b) Procedure. Executive agrees that any arbitration will be administered by the American Arbitration Association (“AAA”) and that a neutral arbitrator will be selected in a manner consistent with its National Rules for the Resolution of Employment Disputes. The arbitration proceedings will allow for discovery according to the rules set forth in the National Rules for the Resolution of Employment Disputes or California Code of Civil Procedure. Executive agrees that the arbitrator shall have the power to decide any motions brought by any party to the arbitration, including motions for summary judgment and/or adjudication and motions to dismiss and demurrers, prior to any arbitration hearing. Executive agrees that the arbitrator shall issue a written decision on the merits. Executive also agrees that the arbitrator shall have the power to award any remedies, including attorneys’ fees and costs, available under applicable law. Executive understands the Company will pay for any administrative or hearing fees charged by the arbitrator or AAA except that Executive shall pay the first $200.00 of any filing fees associated with any arbitration Executive initiates. Executive agrees that the arbitrator shall administer and conduct any arbitration in a

manner consistent with the Rules and that to the extent that the AAA’s National Rules for the Resolution of Employment Disputes conflict with the Rules, the Rules shall take precedence.

(c) Remedy. Except as provided by the Rules, arbitration shall be the sole, exclusive and final remedy for any dispute between Executive and the Company. Accordingly, except as provided for by the Rules, neither Executive nor the Company will be permitted to pursue court action regarding claims that are subject to arbitration. Notwithstanding, the arbitrator will not have the authority to disregard or refuse to enforce any lawful Company policy, and the arbitrator shall not order or require the Company to adopt a policy not otherwise required by law that the Company has not adopted.

(d) Availability of Injunctive Relief. In addition to the right under the Rules to petition the court for provisional relief, Executive agrees that any party may also petition the court for injunctive relief where either party alleges or claims a violation of this Agreement or the Confidentiality Agreement or any other agreement regarding trade secrets, confidential information, nonsolicitation or Labor Code §2870. In the event either party seeks injunctive relief, the prevailing party shall be entitled to recover reasonable costs and attorneys’ fees.

(e) Administrative Relief. Executive understands that this Agreement does not prohibit Executive from pursuing an administrative claim with a local, state or federal administrative body such as the Department of Fair Employment and Housing, the Equal Employment Opportunity Commission or the workers’ compensation board. This Agreement does, however, preclude Executive from pursuing court action regarding any such claim.

(f) Voluntary Nature of Agreement. Executive acknowledges and agrees that Executive is executing this Agreement voluntarily and without any duress or undue influence by the Company or anyone else. Executive further acknowledges and agrees that Executive has carefully read this Agreement and that Executive has asked any questions needed for Executive to understand the terms, consequences and binding effect of this Agreement and fully understand it, including that Executive is waiving Executive’s right to a jury trial. Finally, Executive agrees that Executive has been provided an opportunity to seek the advice of an attorney of Executive’s choice before signing this Agreement.

16. Integration. This Agreement, together with the Option Plan, Option Agreement and the Confidential Information Agreement represents the entire agreement and understanding between the parties as to the subject matter herein and supersedes all prior or contemporaneous agreements whether written or oral. No waiver, alteration, or modification of any of the provisions of this Agreement will be binding unless it is in writing and specifically mentions this Section 16 and it is signed by duly authorized representatives of the parties hereto.

17. Waiver of Breach. The waiver of a breach of any term or provision of this Agreement, which must be in writing, shall not operate as or be construed to be a waiver of any other previous or subsequent breach of this Agreement.

18. Headings. All captions and section headings used in this Agreement are for convenient reference only and do not form a part of this Agreement.

19. Tax Withholding. All payments made pursuant to this Agreement will be subject to withholding of applicable taxes.

20. Governing Law. This Agreement will be governed by the laws of the State of California (with the exception of its conflict of laws provisions).

21. Acknowledgment. Executive acknowledges that he has had the opportunity to discuss this matter with and obtain advice from his private attorney, has had sufficient time to, and has carefully read and fully understands all the provisions of this Agreement, and is knowingly and voluntarily entering into this Agreement.

22. Counterparts. This Agreement may be executed in counterparts, and each counterpart shall have the same force and effect as an original and shall constitute an effective, binding agreement on the part of each of the undersigned. IN WITNESS WHEREOF, each of the parties has executed this Agreement, in the case of the Company by their duly authorized officers, as of the day and year first above written.

COMPANY:

NATUS MEDICAL, INC.