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                                                                   EXHIBIT 10.19

December 10, 2003

Mr. Philip A. Theodore
160 Rumson Road
Atlanta, Georgia 30305

Dear Phil:

I am pleased on behalf of Serologicals Corporation (the "Corporation") to offer
you ("you" or the "Executive") employment (the "Employment") on the terms set
forth herein (the "Offer").

1. Position, Duties and Responsibilities.

         a. You shall serve as the Vice President, General Counsel and Corporate
Secretary and shall be responsible for the duties as agreed between you and the
President and Chief Executive Officer, which will be outlined in a job
description to be finalized shortly after your arrival. You shall report to the
President and Chief Executive Officer of the Corporation and shall be an officer
of the Corporation. You shall also be a member of the Corporation's Operating
Committee.

         b. You will devote all your business time and attention to the business
and affairs of the Corporation and its subsidiaries consistent with your
position. Nothing herein, however, shall preclude you from engaging in
charitable and community affairs, or giving attention to your investments
provided that such activities do not interfere with the performance of your
duties and responsibilities enumerated herein.

         c. Except as otherwise specifically stated herein, you shall be subject
to all of the requirements and provisions described in the Corporation's
employee handbook, as it may be amended from time-to-time.

         d. Following any termination of your employment, upon the request of
the Corporation, you shall reasonably cooperate with the Corporation in all
matters relating to the winding up of pending work on behalf of the Corporation
and the orderly transfer of work to other employees of the Corporation. You
shall also reasonably cooperate in the defense of any action brought by any
third party against the Corporation that relates in any way to your acts or
omissions while employed by the Corporation. The Corporation shall reimburse you
for your reasonable out-of-pocket costs, if any, as permitted by law, incurred
in cooperating with the Corporation.

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Philip A. Theodore
December 10, 2003
Page 2

2. Term.

         Your Employment under these terms shall commence hereunder as soon as
possible but not later than January 1, 2004 (the actual date of commencement
being referred to herein as the "Effective Date") and continue for successive
one (1) year periods, unless otherwise terminated pursuant to the provisions
hereof.

3. Compensation and Related Matters.

         a. Base Salary. You shall be paid a base salary (the "Base Salary")
equal to two hundred fifty-five thousand dollars ($255,000) per year. The Base
Salary shall be payable to you in the manner and on the date(s) on which the
Corporation pays its other executives, but in no event less frequently than
monthly. Based upon performance, you shall be eligible for a salary review six
(6) months after the Effective Date.

         b. Incentive Compensation. You shall be entitled to an annual bonus in
accordance with and subject to your achievement of the Critical Success Factors,
plus other objectives, to be developed and mutually agreed upon by you and the
President and Chief Executive Officer, subject to the Board of Directors
authorizing the payment of such bonus for the given year. You shall also be
eligible to participate in such bonus and incentive compensation plans of the
Corporation, if any, in which other Vice President-level employees of the
Corporation are generally eligible to participate, as the Corporation's Board of
Directors ("Board") or a Committee thereof shall determine from time-to-time in
its sole discretion, subject to and in accordance with the terms and provisions
of such plans. It is understood that should you commence Employment under these
terms, you will be eligible for a bonus for the year 2004.

         c. Employee Benefit Programs. You shall be eligible to participate in
the employee benefit programs (subject to their respective terms) now provided
or as may hereinafter be provided by the Corporation to its executives. Current
benefit programs include:

         -        Group Health Insurance

         -        Corporation Paid Life Insurance (two times your annual salary)

         -        Supplemental and Dependent Supplemental Life Insurance

         -        Serologicals Corporations' Employees Retirement Plan - 401(k)

         -        Short-term Disability Insurance

         -        Long-term Disability Insurance

         -        Flexible Spending Account (Medical and Dependent Care)

         -        Serologicals Corporation's Employee Stock Purchase Plan

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Philip A. Theodore
December 10, 2003
Page 3

         d. Stock Options. On the Effective Date you will be granted a
non-qualified employee stock option under the Corporation's Stock Incentive Plan
(the "Stock Incentive Plan") to purchase fifty thousand (50,000) shares of the
Corporation's $.01 par value common stock at an initial exercise price equal to
the fair market value of such stock on the Effective Date ("Options"). The
Options shall have a term of six (6) years and, so long as you are then employed
by the Corporation, the right to exercise the Options shall vest and be fully
exercisable at the rate of twenty-five percent (25%) per year commencing on the
first anniversary of the Effective Date. Such Options shall be issued pursuant
to a stock option agreement entered into by you and the Corporation and shall be
subject to all the other terms and conditions contained in the Stock Incentive
Plan, the provisions of which shall be determined in the sole discretion of the
Board or a committee thereof. You acknowledge that the Corporation and you
understand that this stock option grant is anticipated to be the only such grant
for a period of two (2) years from the Effective Date.

         e. Reimbursement of Expenses. It is contemplated that in connection
with your Employment hereunder, you may be required to incur business,
entertainment and travel expenses. The Corporation agrees to promptly reimburse
you in full for all reasonable out-of-pocket business, entertainment and other
related expenses (including all expenses of travel and living expenses while
away from home on business or at the request of, and in service of, the
Corporation) incurred or expended by you incident to the performance of your
duties hereunder, provided that you properly account for such expenses in
accordance with the policies and procedures established by the Board and
applicable to the executives of the Corporation.

         f. Paid Time Off. You shall be entitled, in each calendar year of your
Employment, to the number of paid vacation days determined by the Corporation
from time-to-time to be appropriate for its executives, but in no event less
than four (4) weeks in any such year during your Employment (pro-rated, as
necessary, for partial calendar years during your Employment). You may take your
allotted vacation days at such times as are mutually convenient for the
Corporation and you, consistent with the Corporation's vacation policy in effect
with respect to its executives. You shall also be entitled to all paid holidays
given by the Corporation to its executives.

4. Termination.

         a. Disability of the Executive. In the event of your incapacity or
inability to perform your services as contemplated herein for an aggregate of
ninety (90) days during any twelve (12) month period due to the fact that your
physical or mental health shall have become impaired so as to make it impossible
in the judgment of the Corporation for you to perform the duties and
responsibilities contemplated for you hereunder, the Corporation shall have the
right to declare, upon two (2) weeks prior written notice rendered to you, a
disability termination, whereupon you shall receive (if you are entitled
thereto) the short and/or long-term disability benefits provided by the
Corporation. In the event you have commenced receiving benefits under the
Corporation's disability plans, until termination of your employment under this
Section 4(a), the Corporation shall not be obligated to pay to you with regard
to Base Salary an amount greater than the difference between your Base Salary
then in effect and any such disability benefits you are then receiving.

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Philip A. Theodore
December 10, 2003
Page 4

         b. Death of the Executive. In the event you die during your Employment
hereunder, your Employment shall automatically terminate without notice on the
date of your death, except that your estate shall receive the death benefits, if
any, provided by the Corporation.

         c. Termination by the Corporation for Cause. Nothing herein shall
prevent the Corporation from terminating your Employment for Cause (as defined
below). From and after the date of such termination, you shall no longer be
entitled to receive the Base Salary or any other compensation which would have
otherwise been due and all Options shall terminate immediately. Any rights and
benefits that you may have in respect to any other compensation or any employee
benefit plans or programs of the Corporation shall be determined in accordance
with the terms of such other compensation arrangements, plans or programs, and
in any event, you shall have no rights or benefits under any arrangement, plan
or program unless such arrangement, plan or program is in writing and you are
specified as a participant therein. The term "for Cause", as used herein, shall
mean (i) an act of dishonesty causing harm to the Corporation or any subsidiary;
(ii) the knowing disclosure of confidential information relating to the
Corporation's or any subsidiary's business; (iii) habitual drunkenness or
narcotic drug addiction; (iv) conviction of, or a plea of nolo contendere with
respect to, a felony; (v) the willful refusal to perform, or the gross neglect
of, the duties assigned to the Executive; (vi) the Executive's willful breach of
any law that, directly or indirectly, affects the Corporation or any subsidiary;
(vii) the Executive's material breach of his duties following a Change in
Control that do not differ in any material respect from the Executive's duties
and responsibilities during the 90-day period immediately prior to such Change
in Control (other than as a result of incapacity due to physical or mental
illness), which is demonstrably willful and deliberate on the Executive's part,
which is committed in bad faith or without reasonable belief that such breach is
in the best interests of the Corporation and which is not remedied in a
reasonable period after receipt of written notice from the Corporation
specifying such breach. Termination of employment pursuant to this Section 4(c)
shall be made to the Executive by, and be effective upon, written notice from
the President/C.E.O. or the Board.

         d. All Other Terminations by the Corporation. Notwithstanding the
foregoing, the Corporation may terminate your employment at any time. If your
employment is terminated for any reason other than "for Cause", death or
disability, you shall continue to receive your current Base Salary for a period
of twelve (12) months from the date of such termination. In addition, you shall
be eligible to elect COBRA coverage and only pay an amount equal to the employee
contribution typically paid for your type of medical, dental and vision
coverage. The Corporation will pay the remaining costs associated with COBRA
coverage for the 12-month period. After twelve months, you can continue COBRA
coverage at your total cost.

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Philip A. Theodore
December 10, 2003
Page 5

5. Nondisclosure.

         You acknowledge and agree that, during your employment by the
Corporation hereunder, you have or will come to have knowledge and information
with respect to trade secrets or confidential or secret plans, projects,
materials, business methods, operations, techniques, customers, employees,
donors, products, processes, financial conditions, policies and accounts of the
Corporation with respect to the business of the Corporation ("Confidential
Information.") You agree that you will not at any time divulge, furnish or make
accessible to anyone (other than in the regular course of your performance of
services for the benefit of the Corporation, its successors or assigns) any
Confidential Information. Notwithstanding the foregoing, Confidential
Information shall not include any information which (i) is known generally to
the public (other than as a result of unauthorized disclosure), (ii) was
available to you on a non-confidential basis prior to its disclosure to you by
the Corporation or (iii) is required to be disclosed pursuant to the valid order
of a governmental agency or a judicial court of competent jurisdiction, in which
case you shall give prompt written notice to the Corporation of such requirement
so that the Corporation may take such action as it deems appropriate.

6. Non-Compete and Non-Solicitation.

         As a material inducement to the Corporation to enter into this letter,
you agree that at all times during your Employment and for a period of twelve
(12) months after the termination of your Employment, you will not (i) act in a
capacity similar to that in which you shall have served in the Corporation for
any Competing Business or serve in a capacity in any such Competing Business
that would entail your functioning as a sales and marketing executive for a
Competing Business, or (ii) in any way, directly or indirectly, compete with the
business of the Corporation, solicit, divert, or take away or attempt to
solicit, divert, or take away customers of, the business of, or any of the
donors of, the Corporation that dealt with the Corporation during your
Employment. Competing Business means another business engaged in the
business(es) engaged in by the Corporation at any time within one year of or at
the time of your termination.

         You agree that during your Employment and for a period of twelve (12)
months after the termination for any reason of your Employment, you will not
within the United States of America, directly, or indirectly through any means,
including a business entity in which you have an ownership interest, request or
induce any other employee of the Corporation or its affiliates or any donor to
the Corporation or its affiliates to terminate their relationship with the
Corporation or its affiliates and enter into a similar relationship with another
business entity engaged in a business similar to the Corporation's.

7. Executive Creation and Ideas.

         a. You will maintain current and adequate written records on the
development of, and disclose to the Corporation all Creations (as herein
defined). "Creations" shall mean all ideas, potential marketing and sales
relationships, inventions, copyrightable expression, research, plans for
products or services, marketing plans, reports, strategies, processes, computer
software (including, without limitation, source code), computer programs,
original works of authorship, characters, know-how, trade

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Philip A. Theodore
December 10, 2003
Page 6

secrets, information, data, developments, discoveries, improvements,
modifications, technology, algorithms, database schema, designs and drawings,
whether or not subject to patent or copyright protection, made, conceived,
expressed, developed, or actually or constructively reduced to practice by you
solely or jointly with others during your employment with the Corporation, which
refer to, are suggested by, or result from any work which you may perform during
your employment, or from any information obtained from the Corporation or any
affiliate of the Corporation. 'Creations,' however, shall not include the
general business planning concepts, strategies or processes, including, but not
limited to, those utilized by you in any prior employment.

         b. The Creations shall be the exclusive property of the Corporation,
and you acknowledge that all of said Creations shall be considered as "work made
for hire" belonging to the Corporation. To the extent that any such Creations,
under applicable law, may not be considered work made for hire by you for the
Corporation, you hereby agree to assign and, upon its creation, automatically
and irrevocably assign to the Corporation, without any further consideration,
all right, title and interest in and to such materials, including, without
limitation, any copyright, other intellectual property rights, moral rights, all
contract and licensing rights, and all claims and causes of action of any kind
with respect to such materials. The Corporation shall have the exclusive right
to use the Creations, whether original or derivative, for all purposes without
additional compensation to you. At the Corporation's expense, you will
reasonably assist the Corporation in every reasonably proper way to perfect the
Corporation's rights in the Creations and to protect the Creations throughout
the world, including, without limitation, executing in favor of the Corporation
or any designee(s) of the Corporation patent, copyright, and other applications
and assignments relating to the Creations.

         c. Should the Corporation be unable to secure your signature on any
document necessary to apply for, prosecute, obtain, or enforce any patent,
copyright, or other right or protection relating to any Creation, whether due to
your mental or physical incapacity or any other cause, you hereby irrevocably
designate and appoint the Corporation and each of its duly authorized officers
and agents as your agent and attorney in fact, to act for and in your behalf and
stead and to execute and file any such document, and to do all other lawfully
permitted acts to further the prosecution, issuance, and enforcement of patents,
copyrights, or other rights or protections with the same force and effect as if
executed and delivered by you.

         d. Because of the difficulty of establishing when any idea, process or
invention is first conceived or developed by you, or whether it results from
access to Confidential Information or the Corporation's equipment, supplies,
facilities, and data (collectively, "Corporation Information"), you agree that
any idea, invention, research, plan for products or services, marketing plan,
computer software (including, without limitation, source code), computer
program, original work of authorship, character, know-how, trade secret,
information, data, developments, discoveries, technology, algorithm, design,
patent or copyright, or any improvement, rights, or claims (an "Idea") related
to the foregoing, which refer to, are suggested by, or result from any work
which you performed during your employment with the Corporation or from any
Corporation Information, shall be presumed to be a Creation if it is conceived,
developed, used, sold, exploited or reduced to practice by you or with your aid
within one (1) year after

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Philip A. Theodore
December 10, 2003
Page 7

termination of employment. This paragraph, however, shall not apply to anything
that is specifically excepted from the definition of "Creations" in the last
sentence of Section 7(a). You can rebut the above presumption if you prove that
the idea, process or invention (a) was first conceived or developed after
termination of employment, (b) was conceived or developed entirely on your own
time without using any Corporation Information, and (c) did not result from any
work performed by you for the Corporation.

8. Injunctive Relief/Survival.

         You agree that any breach of Section 5, 6 or 7 will cause irreparable
damage to the Corporation and that, in the event of such breach, the Corporation
will have, in addition to any and all remedies of law, including rights which
the Corporation may have to damages, the right to equitable relief including, as
appropriate, all injunctive relief or specific performance or other equitable
relief. You understand and agree that the rights and obligations set forth in
Sections 5 through 10 of this Agreement shall survive the termination or
expiration of this Agreement.

9. Corporation Resources.

         You may not use any of the Corporation's equipment for personal
purposes without written permission from the Corporation. You may not give
access to the Corporation's offices or files to any person not in the employ of
the Corporation without written permission of the Corporation.

10. Miscellaneous.

         a. General. This Agreement supersedes and replaces any existing
agreement between the Executive and the Corporation relating generally to the
same subject matter, and may be modified only in a writing signed by the parties
hereto. Failure to enforce any provision of the Agreement shall not constitute a
waiver of any term herein. The Executive agrees that he will not assign,
transfer, or otherwise dispose of, whether voluntarily or involuntarily, or by
operation of law, any rights or obligations under this Agreement. Any purported
assignment, transfer, or disposition shall be null and void. Nothing in this
Agreement shall prevent the consolidation of the Corporation with, or its merger
into, any other corporation, or the sale by the Corporation of all or
substantially all of its properties or assets, or the assignment by the
Corporation of this Agreement and the performance of its obligations hereunder.
Subject to the foregoing, this Agreement shall be binding upon and shall inure
to the benefit of the parties and their respective heirs, legal representatives,
successors, and permitted assigns, and shall not benefit any person or entity
other than those enumerated above.

         b. Governing Law. This letter is to be governed by and interpreted in
accordance with the laws of the State of Georgia applicable to agreements made
and to be performed within that State except as provided herein.

         c. No Attorney Provided. The Corporation advises you that it is not
providing legal advice in connection with your acceptance and execution hereof.
You

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Philip A. Theodore
December 10, 2003
Page 8

acknowledge (a) that you have consulted with or have had the opportunity to
consult with independent counsel of your own choice concerning this Agreement
and have been advised to do so by the Corporation, and (b) that you have read
and understand the Agreement, are fully aware of its legal effect, and have
entered into it freely based on your own judgment.

         d. Affiliate. References to the "Corporation" hereunder shall include
"affiliates" thereof, as such term is defined in Rule 405 under the Securities
Act of 1933, as amended. The Corporation shall have the right to designate as
your employer hereunder any affiliate of which the Executive shall have
significant operating or managerial responsibility or any other affiliate to
which the Executive agrees.

         e. Severability. If any provision of this letter shall be determined to
be invalid, illegal or unenforceable in whole or in part, all other provisions
hereof shall remain in full force and effect to the fullest extent permitted by
law.

         f. Expiration. This Offer will expire at 5:00 p.m. EST time on December
12, 2003 unless you execute this letter and return it to Robert P. Collins, Vice
President, Human Resources prior to that time.

         g. Contingencies. This Offer is contingent upon satisfactory drug
screen results, pre-employment background check and references.

Please indicate your acceptance of this Offer by signing in the space provided
below.

Sincerely,

SEROLOGICALS CORPORATION

/s/ David A. Dodd

David A. Dodd
President and Chief Executive Officer

                                          ACKNOWLEDGED AND AGREED this 10 day of
                                          December, 2003.

                                                /s/ Philip A. Theodore
                                          --------------------------------------
                                                Philip A. Theodore