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                                                                   Exhibit 10.13

                              EMPLOYMENT AGREEMENT

         EMPLOYMENT AGREEMENT (Agreement) entered into as of the 29th day of
November, 1999 by and between I-Trax.com, Inc., a corporation organized and
existing under the laws of the State of Delaware (Company), and Michael
O'Connell, M.D., an individual residing in the State of Colorado (Employee).

                                    Recitals

         The Company wishes to employ the Employee, and the Employee wishes to
be employed by the Company, on the terms and conditions set forth herein.

         The parties therefore agree as follows:

         1. Services.

            1.1 Duties. The Company hereby employs the Employee as its Chief
Medical Officer. Subject to the direction and authorization of the Company's
board of directors, the Employee shall perform such functions and undertake all
responsibilities associated with such position.

            1.2 Extent of Services. The Employee shall devote his full time and
best efforts to the business and affairs of the Company and to the promotion of
its interests.

            1.3 No Conflict. The Employee represents that his or her employment
hereunder and compliance with the terms and conditions of this Agreement will
not conflict with or result in the breach of any agreement to which he or she is
a party or may be bound.

         2. Term.

         The term of this Agreement shall commence on the date hereof and end on
29 November, 2002, unless sooner terminated as provide in this Agreement.

         3. Compensation.

         3.1 Base Compensation; Bonus. As compensation for the services to be
rendered by the Employee hereunder, the Company shall pay the Employee a salary
at the rate of $85,000 per calendar year in accordance with the Company's
payroll practices. The Company will review the Employee's compensation from time
to time during the term of this Agreement and, at the discretion of the
president of the Company, in consultation with its board of directors, may
increase [or decrease] the Employee's base compensation based upon his or her
performance, the financial condition of the Company, and other relevant factors.
In addition, the Company may pay to the

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Employee such cash bonus(es), if any, as may be determined by the board of
directors of the Company from time to time.

         3.2 Other Compensation. It is agreed that, in addition to the
compensation set forth above, as consideration for future contributions to the
Company Employee shall be the immediate recipient and beneficial owner of 100,
000 shares of the common stock of the Company, on the same basis and at the same
valuation as certain other founding management officers who received stock for
similar consideration in September and October of 1999. Further, it is agreed
that the Company shall reserve an additional 100, 000 shares of the Company's
common stock for Employee in its Incentive Stock Ownership Plan ("ISOP"), in
which shares Employee shall become vested, in increments to be determined, such
that at the conclusion of three years from execution of this Agreement Employee
may be fully vested in such shares. Such shares shall be in addition to shares
obtained by Employee through performance bonus or other process established in
connection with the ISOP.

         3.3 Bonus on Sales. In addition to the foregoing, it is agreed that
Employee shall be entitled to a sales bonus for sales of the Company's
enterprise application systems for which Employee is determined to be primarily
responsible. Such bonus shall be equivalent to a commission of six percent (6%)
on the revenue realized from such sales net of sales costs and expenses, gross
receipts taxes, and capital cost recovery. Employee shall notify the Company, in
writing or by confirmed e-mail, in advance of closing, of prospective sales for
which Employee expects to claim responsibility for purposes of such bonus.
Employee's compensation under this section shall be due as and when the net
revenues on which it shall be based are realized by the Company. Employee may be
paid such bonuses in cash or in the form of appropriately valued options in the
common stock of the Company, or both, from time to time as Employee and the
Company shall agree. Absent agreement, such bonuses shall be in cash.

         4. Expenses.

         The Employee is authorized to incur reasonable expenses for promoting
the business of the Company, including expenses for meals, travel,
entertainment, and similar items. The Company shall reimburse the Employee for
reasonable out-of-pocket expenses incurred by the Employee in performing
services pursuant to this Agreement promptly after receipt of a written
statement from the Employee which itemizes such expenses in reasonable detail,
together with a receipt for any individual expense in excess of $50. In no event
shall the Employee incur any individual expense in excess of $500, or any group
of related expenses in excess of $5,000, without the prior approval of the
president or chief financial officer of the Company. Use by the Employee of his
or her personal vehicle for the business of the Company shall be reimbursed at
the maximum rate per mile allowed by the Internal Revenue Service from time to
time.

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         5. Benefits.

         5.1 Benefit Plans. The Employee shall be entitled to participate in,
and receive benefits from, any insurance, medical, disability, or other employee
benefit plan of the Company, if any, which may be in effect at any time during
the term of this Agreement and which shall be generally available to the
Employee on terms no less favorable than to other management employees of the
Company.

         5.2 Vacation. The Employee shall be entitled during each calendar year
during the term of this Agreement to a vacation of three weeks, with pay, at
times reasonably agreeable to both the Company and the Employee. Unused vacation
time, if any, shall not cumulate from year to year.

         6. Employee's Nondisclosure.

         (a) The Employee expressly agrees that, without the prior approval of
the board of directors of the Company, he or she shall not, at any time during
the term of this Agreement or after its termination, on his or her own behalf or
as a partner, officer, director, trustee, employee, agent, or member of any
person, firm, corporation, or other entity, use or disclose to any person, firm,
corporation, or other entity, or otherwise employ his or her knowledge of the
products and business of, or any trade secrets or other confidential information
as to the operations, products, or customers of, the Company, unless (i)
necessary to the performance of this Agreement and in furtherance of the
Company's best interest or (ii) already in the public domain or generally known
in the industry.

         (b) All documents, records, or similar items, whether in writing or in
electronic or digitized form, relating to the business of the Company shall
remain the exclusive property of the Company and shall not be removed from the
premises of the Company without its prior written approval.

         (c) The provisions of this Section 6 shall survive the termination of
this Agreement.

         7. Inventions.

         (a) If at any time or times during the term of this Agreement,

             (i) the Employee shall (either alone or with others) make,
         conceive, discover, reduce to practice or become possessed of any
         invention, modification, discovery, design, development, improvement,
         process, formula, data, technique, know-how, secret, or intellectual
         property right whatsoever or any interest therein (whether or not
         patentable or registrable under copyright or similar statutes or
         subject to analogous protection) that relates directly to medical
         information systems, software or databases, or results from tasks
         assigned to the Employee by the Company (herein called "Inventions"),
         and

             (ii) (A) in connection therewith, the Employee used equipment,
         supplies, facilities or trade secret information of the Company, or (B)
         in connection therewith, used hours for

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         which he was to be or was compensated by the Company hereunder, or (C)
         which relate at the time of conception or reduction to practice thereof
         the business of the Company or to its actual or demonstrably
         anticipated research and development, or (D) which result from any work
         performed by him for the Company,

such Inventions and the benefits thereof shall immediately become the sole and
absolute property of the Company and its assigns, and the Employee shall
promptly disclose assign to the Company (or any persons designated by it) each
such Invention and benefits or rights resulting therefrom to the Company and its
assigns without compensation and shall communicate, without cost or delay, and
without publishing the same, all available information relating thereto (with
all necessary plans, models, software code or interface designs) to the Company.

         (b) The Employee will also promptly disclose to the Company, and the
Company hereby agrees to receive all such disclosures in confidence, any other
invention, modification, discovery, design, development, improvement, process,
formula, data, technique, know-how, secret or intellectual property right
whatsoever or any interest therein directly in and limited to the fields of
medical information systems, software or databases (whether or not patentable or
registrable under copyright or similar statutes or subject to analogous
protection) made, conceived, discovered, reduced to practice or possessed by the
Employee (either alone or with others) at any time or times during the term of
this Agreement for the purpose of determining whether they constitute
"Inventions" as defined herein.

         (c) Upon disclosure of each Invention to the Company, during the term
of this Agreement and at any time thereafter, the Employee will, at the request
and cost of the Company, sign, execute, make and do all such deeds, documents,
acts and things as the Company and its duly authorized agents may reasonably
require:

             (i) to apply for, obtain and vest in the name of the Company alone
         (unless the Company otherwise directs) patents, copyrights or other
         similar protection in any country throughout the world and when so
         obtained or vested to renew and restore the same; and

             (ii) to defend any opposition proceedings in respect of such
         applications and any opposition proceedings or petitions or
         applications for revocation of such letters patent, copyright or other
         analogous protection.

         In the event the Company is unable, after reasonable effort, to secure
the Employee's signature on any patents, copyright, or other protection relating
to an Invention, whether because of the Employee's physical or mental incapacity
or for any other reason whatsoever, the Employee hereby irrevocably designates
and appoints the Company and its duly authorized officers and agents as the
Employee's agent and attorney-in-fact, to act for and in the Employee's behalf
and stead to execute and file any such application or applications and to do all
other lawfully permitted acts to further the prosecution and issuance of
patents, copyright or other protection thereon with the same legal force and
effect as if executed by the Employee.

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         (d) The Employee will keep and maintain adequate and current records of
all such Inventions and all items that fall within the scope of paragraph (b)
above, in the form of memoranda, notes, sketches, drawings, reports, computer
code, or computer software relating thereto, which records shall be and remain
the property of and available to the Company at all times. Upon termination of
this Agreement, all records of Inventions and such other items in the form of
memoranda, notes, sketches, drawings, reports, computer programs, computer
software, technology and applications thereof, or the like, including all copies
thereof, then in the Employee's possession, whether prepared by the Employee or
others, will be left with the Company.

         (e) The Employee represents that the inventions identified in the
pages, if any, attached hereto comprise all the unpatented inventions or
developments which the Employee has made or conceived prior to the date of this
Agreement, which inventions are excluded from this Agreement. The Employee
understands that it is necessary to list only the title of such invention
itself. IF THERE ARE NO SUCH UNPATENTED INVENTIONS TO BE EXCLUDED, THE EMPLOYEE
SHOULD INITIAL HERE.

         8. Covenant Not to Compete.

         During the term of this Agreement and for a period of 24 months
following its termination (unless this Agreement is terminated by the Employee
pursuant to Section 10.5), the Employee shall not, without the prior written
approval of the Company, directly or indirectly

         (a) carry on or participate in as owner, employee, agent, or otherwise
any business in competition with that conducted or engaged in by the Company;

         (b) solicit, for the Employee's own account or for the account of
others, orders for products or services of a kind similar to those provided by
the Company during the term of this Agreement from any party which was a client
or customer of the Company or which the Company was actively soliciting to be a
customer or client during the 120-day period preceding the date of termination
of this Agreement; or

         (c) urge any customer or client or potential customer or client of the
Company to discontinue business, in whole or in part, or not to do business,
with the Company.

         9. Remedies.

         9.1 Injunctive Relief. A violation by the Employee of the provisions of
Sections 6, 7, or 8 could cause irreparable injury to the Company, for which
there may be no adequate remedy at law. In the event of a breach or threatened
breach by the Employee of any such provision(s), the Company shall have the
right, in addition to any other remedies available to it at law or in equity, to
enjoin the Employee in a court of equity from violating any such provision(s).

         9.2 No Mitigation. If this Agreement is terminated by the Employee
pursuant to Section 10.5, the Employee shall not be required to mitigate damages
otherwise obtainable from the

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Company as a result thereof, and any income received by the Employee after such
termination shall not reduce the amount of damages otherwise obtainable from the
Company hereunder.

         10. Termination.

         This Agreement shall terminate prior to the expiration of the term set
forth in Section 2 upon the occurrence of any one of the following events.

         10.1 Disability. If the Employee is unable substantially to perform his
or her duties under this Agreement by reason of physical or mental illness,
injury, or incapacity for 120 consecutive days, the Company may terminate this
Agreement and thereupon shall have no further liability or obligation to the
Employee for compensation hereunder except as may be prescribed under the terms
of any benefit plans or arrangements referred to in Section 5. 1. In the event
of a dispute under this Section 10. 1, the Employee agrees to submit to a
physical or mental examination by a licensed physician selected by the Company,
whose decision as to the Employee's disability shall be conclusive and binding
upon the Company and the Employee. The Company shall bear the cost of such
examination.

         10.2 Death. This Agreement shall terminate upon the death of the
Employee and thereafter the Company shall have no further liability or
obligation to the Employee for compensation hereunder except as may be
prescribed under the terms of any benefit plans or arrangements referred to in
Section 5. 1.

         10.3 Cause. The Company may terminate this Agreement without further
liability or obligation to the Employee if the Employee (i) has refused, failed,
or neglected to perform duties or render services hereunder or has performed or
rendered them incompetently; (ii) has engaged in illegal or other wrongful
conduct substantially detrimental to the business or reputation of the Company;
(iii) has developed or pursued interests substantially adverse to the Company;
(iv) is convicted of a crime which constitutes a felony; or (v) has otherwise
materially breached this Agreement.

         10.4 Cessation of Business. The Company may terminate this Agreement
upon at least 60 days notice to the Employee of any of the following events and
thereafter the Company shall have no further liability or obligation to the
Employee for compensation hereunder except as may be prescribed under the terms
of any benefit plans or arrangements referred to in Section 5.1: (i) the sale by
the Company of all or substantially all of its assets to a single purchaser or
to a group of associated purchasers; (ii) the sale, exchange, or other
disposition, in one transaction, of at least two-thirds of the outstanding
shares of common stock of the Company; (iii) the good faith decision by the
Company to terminate its business and liquidate its assets; or (iv) the merger
or consolidation of the Company in a transaction in which the shareholders of
the Company receive less than 50 percent of the outstanding voting shares of the
successor corporation.

         10.5 Breach by Company. The Employee may terminate this Agreement upon
at least 30 days notice to the Company of a material breach by the Company of
Sections 3, 4, or 5 of this

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Agreement. The Employee's exercise of this right to terminate shall not abrogate
the Employee's rights or remedies in respect of the breach giving rise to such
termination.

         10.6 Voluntary Termination by Employee. The Employee may terminate this
Agreement at any time upon at least 60 days notice to the Company, after which
termination the Company shall have no further liability or obligation to the
Employee for compensation hereunder except as may be prescribed under the terms
of any benefit plans or arrangements referred to in Section 5.1.

         11. Notice.

         Any notice required or permitted to be given to a party pursuant to the
provisions of this Agreement shall be in writing and shall be deemed to have
been given on the date of receipt if delivered by messenger to, or if mailed to
such party by registered or certified mail, postage prepaid, at, the address for
such party set forth below (or to such other address or party as such party
shall designate in writing to the other party from time to time):

             If to the Company:

                      I-Trax.com, Inc.
                      Attention: General Counsel
                      Reston Plaza II, 12020 Sunrise Valley Drive, Suite 350
                      Reston, VA 20191

             If to the Employee:

                      5595 S. Emporia Circle
                      Englewood, CO 80111

         12. Modification and Waiver.

         (a) No waiver or modification of this Agreement or of any covenant,
condition, or limitation herein contained shall be valid or effective unless in
writing and duly executed by the party to be charged therewith and no evidence
of any waiver or modification shall be offered or received in evidence of any
proceeding or litigation between the parties arising out of or affecting this
Agreement, or the rights or obligations of the parties hereunder, unless such
waiver or modification is in writing, duly executed as aforesaid.

         (b) The parties further agree that the provisions of paragraph (a)
above may not be waived except as herein set forth. No waiver of any of the
provisions of this Agreement shall be deemed, or shall constitute, a waiver of
any other provision, whether or not similar, nor shall any waiver constitute a
continuing waiver. No waiver of any breach of condition of this Agreement shall
be deemed to be a waiver of any other subsequent breach of condition, whether of
like or different nature.

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         13. Severability.

         If any clause, paragraph, or section of this Agreement be held invalid
or unenforceable, the remaining provisions of this Agreement shall not be
affected thereby and shall be valid and remain enforceable to the extent
permitted by law. Moreover, if any one or more of the provisions in this
Agreement shall for any reason be held to be excessively broad as to duration,
geographical scope, activity, or subject, it shall be construed by limiting and
reducing it, so as to be enforceable to the extent compatible with then
applicable law.

         14. Governing Law.

         This Agreement shall be governed by and construed in accordance with
the laws of the State of Delaware, without giving effect to principles of
conflicts of law.

         15. Entire Agreement.

         This Agreement constitutes the entire agreement between the parties
pertaining to the subject matter hereof and supersedes all prior and
contemporaneous agreements, representations, and understandings, whether oral or
in writing, of the parties. No supplement, modification, or amendment of this
Agreement shall be binding upon the parties hereto unless executed in writing in
accordance with Section 12.

         16. Headings.

         The headings in this Agreement are inserted for convenience of
reference only and shall not be deemed to constitute a part or affect the
meaning of any provision hereof.

         17. Counterparts.

         This Agreement may be executed in one or more counterparts, each of
which shall be deemed to constitute an original but all of which together will
constitute one and the same instrument.

         18. Assignments.

         (a) The Employee may not assign any rights or obligations under this
Agreement without the prior written consent of the Company. This Agreement shall
be binding upon and inure to the benefit of the Employee and his or her heirs,
guardians, executors, administrators, and permitted successors and assigns.

         (b) The Company may not assign any rights or obligations under this
Agreement without the prior written consent of the Employee except to the
surviving corporation in connection with a merger or consolidation involving the
Company or to the purchaser of assets in connection with a sale of all or
substantially all of its assets, so long as the assignee expressly assumes the
Company's

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rights or obligations. This Agreement shall be binding upon and inure to the
benefit of the Company and its permitted successors and assigns.

         (c) This Agreement does not create, and shall not be construed as
creating, any rights enforceable by any person not a party to this Agreement,
except as provided in this Section 18.


         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
day and year first above written.

                                           COMPANY

                                              I-TRAX.COM, INC.


                                              By: /s/ Hans C. Kastensmith
                                                  ------------------------------
                                                  Hans C. Kastensmith, President

                                           EMPLOYEE

                                                  /s/ Michael O'Connell, M.D.
                                                  ------------------------------
                                                  Michael O'Connell, M.D.

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