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                                                                  EXHIBIT 10.23

                                 [Logo]

July 28, 1998

Jeffrey W. Church
14827 Michele Drive
Gleneig, MD 21737

Dear Jeff:

It is with great pleasure that we extend an offer of employment to you for
the position of Chief Financial Officer. We were all very impressed with your
background and experience and we believe that you would be a valuable
addition to the GenVec team. In this position, you will report to Paul H.
Fischer, President and CEO.

The specific terms of this offer are detailed in the enclosed schedule. As
discussed, your start date is on August 24, 1998. Two copies of the GenVec
Confidentiality, Invention and Non-Compete Agreement that must be signed by
each GenVec employee are enclosed.

If the terms of this offer are acceptable to you, please sign and date both
copies of the enclosed schedule and the GenVec Confidentiality, Invention,
and Non-Compete Agreement, keep one of each for yourself and return the other
to me.

This letter and schedule, along with the GenVec Confidentiality, Invention
and Non-Compete Agreement, set forth the terms of your employment with GenVec
and supersedes any prior representations or agreements, whether written or
oral. This agreement may not be modified or amended except by a written
agreement, signed by an officer of GenVec and by you.

Sincerely,

/s/ Paul H. Fischer, Ph.D.
Paul H. Fischer, Ph.D.
President and CEO

enc.

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                                 GenVec, Inc.
                         Terms of At-Will Employment

Employee Name:     Jeffrey W. Church

Position:          Chief Financial Officer

Start Date:        August 24, 1998

Business Hours:    8:30 a.m. - 5:30 p.m.

Salary:            $175,000 per year, to be paid in semi-monthly installments

Bonus:             It is anticipated that a performance bonus of up to 25%
                   may be applicable at the end of the calendar year and if
                   performance milestones are achieved.

Equity:            A new hire grant of 70,000 stock options to purchase
                   shares of Common Stock at a strike price equal to the fair
                   market value as determined by the Board of Directors as of
                   the date of grant will be recommended for Board
                   ratification. Such options will be issued under and
                   subject to the terms and conditions of the Company's
                   Amended and Restated 1993 Stock Option PLan and will begin
                   vesting as of the date of hire.

Salary
Continuation:      Should employment be terminated for any reason other than
                   for cause, salary would continue to be paid for a period
                   of six (6) months from the effective date of such
                   termination. Payments made thereunder would cease if
                   permanent employment is found at the same or greater
                   salary during the 6-month period.

Benefits:          Three (3) weeks vacation.

                   Holidays, as set forth in the company's holiday schedule
                   as well as one (1) personal day, allocated and defined in
                   the Employee Handbook.

                   Health Insurance - Health/dental insurance is provided by
                   American Medical Security Health Insurance Company. This
                   is a PPO system. GenVec covers 80% of the premium cost for
                   each employee.

                   Disability - Short term and long term disability provided

                   Life Insurance - GenVec covers the cost of life insurance
                   to a maximum of $50,000 payout to beneficiaries.

                   Section 125 Plan - GenVec provides for pre-tax withdrawal
                   of employee's salary to cover costs for items such as
                   medical insurance premiums, medical reimbursement and
                   licensed dependent care.

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                   Tuition reimbursement - After 90 days of employment and
                   approval from the employee's manager, GenVec will
                   reimburse the employee for approved courses in accordance
                   with terms listed in the Employee Handbook.

                   401(k) Plan - After six (6) months of employment and at
                   the open enrollment period, an employee, age 21 years or
                   greater and who has worked at least 1,000 hours is eligible
                   to participate in GenVec's 401(k) Plan. Employee
                   contribution is limited to 15% of base salary or to a
                   maximum of $10,000 per year, per Federal law.

At-Will
Employment:        You should be aware that your employment with GenVec is
                   for no specified period and constitutes at-will employment.
                   As a result, you are free to resign at any time, for any
                   reason or for no reason. Similarly, GenVec is free to
                   conclude its employment relationship with you at any time,
                   with or without  cause, and with or without notice.

Agreed to and Accepted By:

/s/ Jeffrey C. Church                      July 29, 1998
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Jeffrey C. Church                      Date<PAGE>

                                                                  EXHIBIT 10.24

GenVec, Inc.
12111 Parklawn Drive
Rockville, MD 20852

     The following confirms an agreement between me and GenVec, Inc. a
Delaware corporation (hereinafter called the "Company"):

     1.  I understand that my employment creates a relationship of confidence
and trust between me and the Company with respect to any information
(hereinafter collectively referred to as "Proprietary Information") possessed
by the Company which the Company desires to or is obligated to keep in
confidence or which has commercial value in the business in which the Company
is engaged. I understand that such Proprietary Information includes, without
limitation, formulas, processes, techniques, test data, strategies, and
financial data, and includes information which I may develop in the course of
my employment. At all times during my employment and thereafter I will keep
in confidence all Proprietary Information, and I will not use or disclose any
Propreitary Information without the Company's prior written consent except as
may be necessary in the ordinary course of my duties as an employee.

     2.  I will promptly disclose to the Company all formulas, processes,
techniques, tests data, improvements conceive, learn or reduce to practice,
either alone or jointly with others, during the period of my employment and
which are related to or useful in the Company's business, and which result
from tasks I am assigned by the Company or from use of Company Proprietary
Information or facilities (hereinafter collectively referred to as
"Inventions").

     3.  I agree that all Proprietary Information, all Inventions and all
patent and other rights related thereto are the sole property of the Company,
and I hereby assign to the Company any rights I may have or acquire in such
Proprietary Information Inventions. I further agree to assist the Company (at
its expense) in every proper way (including execution of patent applications
and other documents) to obtain and enforce patents on any Inventions. I agree
that my obligation to assist the Company in obtaining and endorsing patents
will continue beyond the termination of my employment, but the Company will
compensate me at reasonable rates for the assistance I actually provide at
the Company's request after such termination. I hereby irrevocably appoint
the Company and its duly authorized officers and agents as my agents and
attorneys-in-fact to execute and file all documents and

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perform all other lawful acts related to the foregoing.

     5.  I agree that all documents, equipment and other physical property
furnished to or produced by me in connection with my work as an employee are
the sole property of the Company and I will promptly deliver all such
property to the Company at its request and (whether or not the company so
requests) upon the termination of my employment.

     6.  For the period of twelve months immediately after termination of
employment with the Company, the employee shall not engage in any work or
other activity - whether as owner, stockholder, partner, officer, consultant,
employee or otherwise - involving a product or process similar to the product
or process on which the employee worked for the Company (or any of its
subsidiary or affiliated companies) at any time during the period of two years
immediately prior to termination of employment, if such work or other
activity is then competitive with that of the Company (or any of its
subsidiary or affiliated companies), provided that this restriction shall not
apply if the employee has disclosed to the Company in writing all the known
facts relating to such work or activity and has received a release in writing
from an officer of the Company to engage in such work or activity. However,
if the Company refuses to grant such a written release and if the employee is
unable to obtain employment consistent with his qualifications and experience
solely because of such refusal, then in that event the Company shall make
payments to the employee at the rate of employee's base salary at termination
of employment for each month that the employee has certified that employee
has been unable for such reason to secure such employment, provided that the
obligation of the Company to make such payments shall cease upon whichever is
the first to occur of (a) the date the employee shall obtain employment, (b)
the date on which the Company shall grant a written release to the employee,
or (c) the expiration of twelve months following the termination of
employment: and provided further that no such payment shall be made for any
month for which any payment is made by the Company to the employee under any
other provision of the Agreement. Ownership by the employee of five per cent
or less of the outstanding share of stock of any company either (i) listed on
a national securities exchange or (ii) having at least 100 stockholders shall
not make the employee a "stockholder" within the meaning of that term as used
in this paragraph. Nothing in this paragraph shall limit the rights or
remedies of the Company arising directly or indirectly from such competitive
employment including, without limitation, claims based upon breach of
fiduciary duty, misappropriation, or theft of confidential information.

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     7.  I represent that my performance of this Agreement will not breach
and other agreement or obligation, written or oral, by which I am bound.

     8.  Interpretation and enforcement of this Agreement shall be governed
by the laws of the State of Maryland, the location of the Company's
operations.

     9.  I agree that this Agreement is effective as of the first day of my
employment and is binding upon me, my heirs, executors, administrators and
assigns and shall inure to the benefit of the Company, its successors and
assigns.

                                      Sincerely,

                                      By:
                                         ---------------------------------------
                                         (Employee)

                                      ------------------------------------------
                                      Social Security Number

ACCEPTED AND AGREED TO:

GENVEC, INC.

By:
    ------------------------

Title:
        --------------------

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