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                                                                    Exhibit 10.4




July 2, 2001



Mr. Peter J. Pizzo, III
Serologicals Corporation
5655 Spalding Drive
Norcross, Georgia 30092

Dear Peter:

As we discussed on June 5, 2001, I have determined that your employment with
Serologicals Corporation will be terminated. We will immediately initiate a
search for someone to assume your duties and job responsibilities.

You should promptly begin efforts to secure alternative employment. To assist
you, Serologicals will make available, at its expense, full outplacement
services to you, to be provided by a professional outplacement firm selected by
us, until you find alternative employment or September 30, 2001, whichever is
earlier. Serologicals will be liable for and make payments for all fees and
expenses incurred by the outplacement firm directly to the outplacement firm.
Please contact Diane Miller to make arrangements for initiation of this service.
The following sets forth our mutual commitments:

1.       Serologicals will continue to pay your base salary and provide your
         current health and welfare benefits until the earlier of September 5,
         2001 or the date you elect to leave employment with the company (the
         "Termination Date"). From this date until the Termination Date, you
         will devote your time and attention to the business affairs of the
         Company and conduct business as usual under my direction. The Company
         agrees to grant you reasonable time off with pay to pursue activities
         dedicated to securing alternative employment.

2.       You shall be entitled to all of the benefits provided for in the letter
         agreement between the Company and you dated February 3, 2000 (the
         "Letter Agreement") and in each individual Stock Option Agreement for
         Key Employees between the Company and you which are dated as of October
         14, 1996; January 29, 1997; December 9, 1997; December 31, 1998;
         December 31, 1999 (October 25, 1999 grant); and December 31, 1999
         (February 3, 2000 grant) (collectively the "Option Agreements").
         Specifically, the Company agrees that your termination is pursuant to
         section 3 (d) (1) of the Letter Agreement and is not "for cause."


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Mr. Peter J. Pizzo, III
July 2, 2001
Page 2


3.       For a period of one (1) year from September 5, 2001, you shall continue
         to cooperate with the Company if so requested with respect to the
         continued transition of your duties. The time spent by you for such
         activities shall not exceed eight (8) hours per week, unless mutually
         agreed upon between the Company and you. The Company will reimburse you
         for any out-of-pocket expenses incurred by you with respect to such
         activities.

4.       Provided you remain employed through September 5, 2001 and comply with
         the obligations set forth in paragraph 3 above, any unvested options
         under the Option Agreements dated December 31, 1998 and December 31,
         1999 (February 3, 2000 grant) shall become 100% vested on September 5,
         2002. In addition, you shall have until December 5, 2002 to elect to
         exercise any options under those two Option Agreements. In the event
         you voluntarily leave employment prior to September 5, 2001 or fail to
         comply with the obligations set forth in paragraph 3 above, such
         options shall remain unvested.

5.       You agree to release and forever discharge the Company, its affiliated
         companies, and past and present directors, officers, owners, agents,
         employees or attorneys, from any and all actions, causes of action,
         asserted or unasserted claims and demands whatsoever, in law or in
         equity (hereinafter collectively referred to as "Claims"), whether
         known or unknown, which you may have against the Company based on any
         acts, omissions, transactions or occurrences whatsoever occurring or
         accruing prior to the date of execution of this Agreement, including,
         but not limited to: (i) claims which are related to employment with the
         Company and the termination of employment; (ii) claims for retaliatory,
         wrongful or constructive discharge, intentional or negligent infliction
         of emotional distress, outrageous conduct, invasion of privacy,
         assault, battery, fraud, breach of duty, libel, slander or tortious
         conduct of any kind; and/or (iii) all other claims arising at law or in
         equity.

6.       We shall agree upon the wording of a written statement concerning your
         employment and separation from employment that may be used by both
         parties for any necessary communications related thereto (the
         "Statement"). The Company and you agree that all written or verbal
         representations regarding your employment will consist of the Statement
         or will confirm dates of employment and final position held only with
         no information on performance or reasons for termination. You agree
         that you will not make any statement, verbal or written, that would
         tend to disparage or denigrate the character, professionalism, business
         practices or performance of job duties of the Company or any of its
         directors, officers or employees, or prejudice the Company with respect
         to reputation or business matters.


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Mr. Peter J. Pizzo, III
July 2, 2001
Page 3


If you are in agreement with the terms set forth above, please sign this letter
and return it to me.


I wish you the best in your future endeavors.

Sincerely,



David A. Dodd


                                            ACCEPTED AND AGREED:


                                            /s/ Peter J. Pizzo, III
                                            ------------------------------------
                                            Peter J. Pizzo, III