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NABI BIOPHARMACEUTICALS
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                                                                  EXHIBIT  10.31

                             NABI BIOPHARMACEUTICALS
                      5800 PARK OF COMMERCE BOULEVARD, N.W.
                            BOCA RATON, FLORIDA 33487

                            EFFECTIVE AS OF 11/11/02

Daniel Greenleaf
Basking Ridge, NJ 07920

Dear Dan:

You have agreed to serve as Sr. Vice President, Operations for Nabi
Biopharmaceuticals ("Nabi"). The following are the terms of such employment:

1. TERM: You will serve as a Sr. Vice President, Operations of Nabi for a period
beginning as of the date hereof and ending on 10/31/2005, unless your employment
is sooner terminated as provided below (the "Employment Period"). In the event
that your employment by the Company continues beyond the Employment Period, your
continued employment by the Company shall be on an at will basis and may be
terminated by either party upon thirty (30) days' prior notice unless you and
the Company shall have entered into a written renewal of this Agreement.

2. SALARY: Your salary will be $235,000 per year, payable bi-weekly during the
Employment Period. Your salary will be subject to discretionary annual increases
as determined by Nabi's Board of Directors.

3. BONUS: You will be entitled to participate in Nabi's VIP Management Incentive
Program. Unless the Employment Period is terminated for "cause" pursuant to
Section 7(B)(b) below, bonus compensation shall be pro rated in respect of any
calendar year during which the Employment Period terminates based on the amount
of bonus compensation which would have been payable with respect to such year
per your original VIP Management Incentive Program participation, divided by 12,
times the number of full calendar months during the relevant year you were
employed prior to the termination of the Employment Period. If the Employment
Period is terminated pursuant to Section 7 (B)(b) below, no bonus compensation
is payable with respect to the calendar year during which it is terminated.

Bonus payments shall be payable within 120 days after the end of the relevant
calendar year.

4. AUTO ALLOWANCE: While an employee under the terms of this Agreement, you
shall receive an auto allowance of not less than $900.00 per month.

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5. BENEFITS: During the Employment Period, you will be eligible to participate
in such fringe benefits programs as are accorded to other similarly situated
Nabi employees.

6. DUTIES AND EXTENT OF SERVICES:

(A) During the Employment Period, you agree to devote substantially all of your
working time, and such energy, knowledge, and efforts as is necessary to the
discharge and performance of your duties provided for in this Agreement and such
other reasonable duties and responsibilities consistent with your position as
are assigned to you from time to time by the person to whom you report. You
shall be located primarily in Nabi's Boca Raton, Florida facilities, but shall
travel to other locations from time to time as shall be reasonably required in
the course of performance of your duties.

(B) During the Employment Period, you shall serve as a Sr. Vice President,
Operations with "Operations" being defined as Manufacturing, Sales and
Marketing. You shall have such duties as are delegated to you by the person to
whom you report provided that such duties shall be reasonably consistent with
those duties assigned to executive officers having similar titles in
organizations comparable to Nabi.

7. TERMINATION:

(A) The Employment Period shall terminate upon your death. You may also
terminate the Employment Period upon thirty (30) days' prior written notice to
Nabi. Any termination pursuant to this Section 7(A) shall not affect any bonus
compensation applicable to the year of such termination, provided that any bonus
compensation payable pursuant to Section 3 of this Agreement shall be pro rated
as provided for in Section 3.

(B) Nabi may terminate the Employment Period in the event of (a) your inability
to perform the essential functions of your position, with or without reasonable
accommodation for any three (3) consecutive months as the result of mental or
physical incapacity (Nabi shall determine in good faith whether you are unable
to perform the essential functions of your position). This determination of
disability shall be made by a physician satisfactory to both you and Nabi,
provided that if you and Nabi do not agree on a physician, you and Nabi shall
each select a physician and these two together shall select a third physician,
whose determination as to disability shall be binding on all parties. or (b) for
"cause", which is defined as (i) commission of fraud or embezzlement or other
felonious acts by you, (ii) your refusal to comply with reasonable directions in
connection with the performance of your duties as provided for in Section 6 of
this Agreement after written notice of such failure is delivered to you, (iii)
failure to comply with the provisions of Section 9 or 10 of this Agreement or
(iv) your gross negligence in connection with the performance of your duties as
provided for in this Agreement, which gross negligence causes material damage to
Nabi, provided that, in the event of termination under this clause (b), you
shall receive ten (10) days' written notice prior to termination and a
determination must be made

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by Nabi's Board of Directors or a duly appointed committee of the Board, after
you are afforded an opportunity to be heard, that it is, at the date of such
termination, reasonable to conclude that grounds for such termination under this
clause (b) still exists.

(C) Nabi may otherwise terminate the Employment Period upon thirty (30) days'
prior notice to you.

(D) Your confidentiality and non-competition agreements set forth in Sections 9
and 10 below shall survive the termination of your employment regardless of the
reasons therefor.

8. SEVERANCE

(A) In the event that (a) your employment terminates pursuant to Section 7C or
(b) within thirty (30) days after the expiration of the Employment Period,
either you give notice of termination of employment to the Company or the
Company gives you notice of termination of employment other than for cause (as
defined above) or disability, and provided that within thirty (30) days prior to
the expiration of the Employment Period Nabi had not offered to renew this
Agreement on terms no less favorable to you than the terms then in effect, you
shall receive the benefits set forth in Section 8B, 8C and 8D. In the event your
employment terminates pursuant to Section 7B (a), or as a result of your death,
the benefit set forth in Section 8D shall be initiated.

(B) Based on the effective date of such termination, Nabi will pay you severance
pay of twelve (12) months of your annual base salary as in effect at the time of
such termination ("Severance Pay") and maintain in effect for a twelve (12)
month period such fringe benefits as are accorded to other similarly situated
employees (to the extent allowed under, and subject to the limitations of,
applicable plans). Severance Pay provided for in this paragraph shall be made in
twenty-six (26) equal bi-weekly installments.

(C) The Company shall pay up to $25,000 for outplacement services provided to
you by an organization selected by you.

(D) All non-vested stock options, restricted stock or similar incentive equity
instruments pursuant to the Company's 2000 Employee Non-Qualified Stock Option
Plan and/or successor plans (the "Options") shall immediately vest. All such
"Options" shall be exercisable for one (1) year past termination date, except
that no "Options" shall be exercisable beyond the original "Option" expiration
date. To the extent the terms of any "Options" are inconsistent with this
Agreement, the terms of this Agreement shall control.

(E) All payments or benefits to you under this Section 8 (other than payments or
benefits already accrued and otherwise due under Nabi's employee benefit plans
or programs, or as a result of your death) will not be given unless you execute
(and do not rescind) a written employment termination agreement in a form
prescribed by Nabi, which includes a general release of all claims against Nabi
and related parties with respect to all matters occurring prior to or on the
date of the release, including (but not limited to) employment matters or
matters in connection with your termination.

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9. CONFIDENTIALITY: You acknowledge that your duties as described in Section 6
of this Agreement will give you access to trade secrets and other confidential
information of Nabi and/or its affiliates, including but not limited to
information concerning production and marketing of their respective products,
customer lists, and other information relating to their present or future
operations (all of the foregoing, whether or not it qualifies as a "trade
secret" under applicable law, is collectively called "Confidential
Information"). You recognize that Confidential Information is proprietary to
each such entity and gives each of them significant competitive advantage.

Accordingly, you shall not use or disclose any of the Confidential Information
during or after the Employment Period, except for the sole and exclusive benefit
of the relevant company. Upon any termination of the Employment Period, you will
return to the relevant company's office all documents, computer electronic
information and files, e.g., diskettes, floppies etc. and other tangible
embodiments of any Confidential Information. You agree that Nabi may be
irreparably injured by any actual breach of your confidentiality agreement, that
such injury may not be adequately compensable by monetary damages, and that,
accordingly, the offended company may specifically enforce the provisions of
this Section by application for injunction or similar remedy by any court of
competent jurisdiction without affecting any claim for damages.

10. NON-COMPETITION:

(A) You acknowledge that your services to be rendered are of a special and
unusual character and have a unique value to Nabi the loss of which cannot
adequately be compensated by damages in an action at law. In view of the unique
value of the services, and because of the Confidential Information to be
obtained by or disclosed to you, and as a material inducement to Nabi to enter
into this Agreement and to pay to you the compensation referred to above and
other consideration provided, you covenant and agree that you will not, during
the term of your employment by Nabi and for a period of one (1) year after
termination of such employment for any reason whatsoever, you will not, directly
or indirectly, (a) engage or become interested, as owner, employee, consultant,
partner, through stock ownership (except ownership of less than five percent of
any class of securities which are publicly traded), investment of capital,
lending of money or property, rendering of services, or otherwise, either alone
or in association with others, in the operations, management or supervision of
any type of business or enterprise engaged in any business which is competitive
with any business of Nabi (a "Competitive Business"), (b) solicit or accept
orders from any current or past customer of Nabi for products or services
offered or sold by, or competitive with products or services offered or sold by,
Nabi, (c) induce or attempt to induce any such customer to reduce such
customer's purchase of products or services from Nabi, (d) disclose or use for
the benefit of any Competitive Business the name and/or requirements of any such
customer or (e) solicit any of Nabi's employees to leave the employ of Nabi or
hire or negotiate for the employment of any employee of Nabi. At the time any of
the provisions of Section 8 ("Severance") would be implemented, Nabi will
determine in good faith, and in writing to you, the specific organizations that
it defines as a "Competitive Business."

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(B) You have carefully read and considered the provisions of this Section and
Section 9 and having done so, agree that the restrictions set forth (including
but not limited to the time period of restriction and the world wide areas of
restriction) are fair and reasonable (even if termination is at our request and
without cause) and are reasonably required for the protection of the interest of
Nabi, its officers, directors, and other employees. You acknowledge that upon
termination of this Agreement for any reason, it may be necessary for you to
relocate to another area, and you agree that this restriction is fair and
reasonable and is reasonably required for the protection of the interests of
Nabi, their officers, directors, and other employees.

(C) In the event that, notwithstanding the foregoing, any of the provisions of
this Section or Section 9 shall be held to be invalid or unenforceable, the
remaining provisions thereof shall nevertheless continue to be valid and
enforceable as though invalid or unenforceable parts had not been included
therein. In the event that any provision of this Section relating to time period
and/or areas of restriction shall be declared by a court of competent
jurisdiction to exceed the maximum time period or areas such court deems
reasonable and enforceable, said time period and/or areas of restriction shall
be deemed to become, and thereafter be, the maximum time period and/or area
which such court deems reasonable and enforceable.

(D) With respect to the provisions of this Section, you agree that damages, by
themselves, may be an inadequate remedy at law, that an actual material breach
of the provisions of this Section may cause irreparable injury to the aggrieved
party, and that provisions of this Section 10 may be specifically enforced by
application for injunction or similar remedy in any court of competent
jurisdiction without affecting any claim for damages.

11. MISCELLANEOUS: This Agreement and the rights and obligations of the parties
pursuant to it and any other instruments or documents issued pursuant to it
shall be construed, interpreted and enforced in accordance with the laws of the
State of Florida, exclusive of its choice-of-law principles. This Agreement
shall be binding upon and inure to the benefit of the parties hereto, and their
respective successors and assigns. The provisions of this Agreement shall be
severable and the illegality, unenforceability or invalidity of any provision of
this Agreement shall not affect or impair the remaining provisions hereof, and
each provision of this Agreement shall be construed to be valid and enforceable
to the full extent permitted by law. To the extent any provision of this
Agreement is deemed to be illegal, unenforceable or invalid, the parties shall
in good faith agree upon an alternative provision that effects, to the maximum
extent practicable, the intent of the illegal, unenforceable or invalid
provision. In any suit, action or proceeding arising out of or in connection
with this Agreement, the prevailing party shall be entitled to receive an award
of the reasonable related amount of attorneys' fees and disbursements incurred
by such party, including fees and disbursements on appeal. This Agreement, along
with your offer letter of employment and the Change of Control Agreement, is a
complete expression of all agreements of the parties relating to the subject
matter hereof, and all prior or contemporaneous oral or written understandings
or agreements shall be null and void except to the extent set forth in this
Agreement, your offer letter of employment and the Change of Control Agreement.

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This Agreement cannot be amended orally, or by any course of conduct or dealing,
but only by a written agreement signed by the party to be charged therewith. All
notices required and allowed hereunder shall be in writing, and shall be deemed
given upon deposit in the Certified Mail, Return Receipt Requested, first-class
postage and registration fees prepaid, and correctly addressed to the party for
whom intended at its address set forth under its name below, or to such other
address as has been most recently specified by a party by one or more
counterparts, each of which shall constitute one and the same agreement. All
references to genders or number in this Agreement shall be deemed
interchangeably to have a masculine, feminine, neuter, singular or plural
meaning, as the sense of the context required.


If the foregoing confirms your understanding of our agreements, please so
indicate by signing in the space provided below and returning a signed copy to
us.


                            Nabi Biopharmaceuticals
                            5800 Park of Commerce Boulevard, N.W.
                            Boca Raton, Florida 33487


                            BY: /s/ Thomas McLain
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                               Thomas H. McLain
                               Executive Vice-President, Chief Operating Officer

Accepted and agreed:

 /s/ Daniel Greenleaf
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Daniel Greenleaf
Basking Ridge NJ 07920

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