WASHINGTON, D.C. 20549

                                  SCHEDULE 14A
                                 (RULE 14A-101)

                        SECURITIES EXCHANGE ACT OF 1934
                               (AMENDMENT NO. __)

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                               Filed by: American Medical Security Group, Inc.
                                                       Pursuant to Rule 14a-12
                                     under the Securities Exchange Act of 1934

                        Subject Company: American Medical Security Group, Inc.
                                                   Commission File No. 1-13154

On September 15, 2004, American Medical Security Group, Inc. posted the
following letter on the company's intranet for employee communications and sent
the letter by electronic mail to its employees:

September 15, 2004

Dear AMS Employees:

         By now you're aware of the milestone merger agreement jointly
announced by AMS and PacifiCare early this morning. Because my schedule will
not allow me to immediately share my perspective on this merger with you in
person, this letter will provide some initial thoughts until we can schedule a
State of the Company meeting within the next few days.

         First of all, PacifiCare Health Systems is a Fortune-200 company based
in Cypress, California, and one of the nation's largest consumer health
organizations. Led by Chairman and CEO, Howie Phanstiel, PacifiCare operates
primarily within eight western states and Guam, and has more than three million
health plan members and approximately nine million specialty plan members
nationwide. With more than $12 billion in revenues, PacifiCare offers
individuals, employers and Medicare beneficiaries a variety of consumer-driven
health care and life insurance products.

         It's my view that this is a compelling strategic business combination
that over time will benefit customers, employees and other key constituencies.
Consider these factors:

|X|      In a period of industry consolidation, scale has become an
         increasingly important competitive advantage. This merger will create
         a combined company with greater breadth in terms of membership,
         operations, networks and management expertise.

|X|      PacifiCare has an announced strategy to expand its individual and
         small group businesses - markets where we have long-standing

|X|      On a state-by-state basis, our markets are very complementary, with
         minimal overlap.

|X|      Both organizations have invested in strong service models and are
         committed to tight operational discipline.

|X|      PacifiCare has a broad range of products that may allow us in time to
         expand the health benefit products we distribute.

         Most importantly, PacifiCare has done a detailed analysis of our
business. With that background, they have shared with me plans to keep the AMS
organization intact and to establish our Green Bay operations as a platform for
continued growth in the individual and small group business.

         Along with members of my management team, I have agreed to continue to
run this business for PacifiCare. In addition, the CEO of PacifiCare and I have
already discussed plans to expand our operations here.

         At this early juncture, there are far more questions than answers. The
two companies will now work to close our transaction and join forces as
PacifiCare by the end of the year or early next. During that process, you can
rest assured that we will be diligent in keeping you informed about the merger
process and what it means for employees.

         In the meantime, please approach your jobs on a "business as usual"
basis. Understand that the best way you can contribute to the success of this
exciting new partnership is by continuing to perform your day-to-day job
activities at the highest possible level. That's something we've become
accustomed to in this organization.

         You have my sincerest thanks for your past and future support.

/s/ Sam Miller
Sam Miller
AMS Chairman, President & Chief Executive Officer

PacifiCare Health Systems and American Medical Security Group and their
respective officers and directors may be deemed to be participants in the
solicitation of proxies from shareholders of American Medical Security Group,
Inc. with respect to the transactions contemplated by the merger agreement
between PacifiCare and American Medical Security Group. Information regarding
the companies' officers and directors is included in their respective
definitive proxy statements for their 2004 annual meetings of stockholders
filed with the Securities and Exchange Commission in April 2004. These
documents are available free of charge at the Securities and Exchange
Commission web site at www.sec.gov, from PacifiCare at pacificare.com and from
AMS at eAMS.com. Investors and security holders may obtain more detailed
information about who may be deemed participants in the solicitation of proxies
by reading the AMS proxy statement when it becomes available.

Furthermore, investors and security holders of American Medical Security Group
are urged to read American Medical Security Group's proxy statement regarding
the proposed merger when it becomes available. It will contain important
information about the merger and the transactions contemplated by the merger
agreement. Investors and securities holders of American Medical Security Group
may obtain a free copy of American Medical Security Group's proxy statement
when it is available and other documents filed with the Securities and Exchange
Commission at the Commission's web site at www.sec.gov. American Medical
Security Group's proxy statement and these other documents may also be obtained
for free from American Medical Security Group at eAMS.com.