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. transmitted the
following letter to agents of the company by broadcast fax or electronic mail:

[Letterhead of Samuel V. Miller]

September 15, 2004

Dear AMS Agent:

         Accompanying this letter is a press release announcing the completion
of a definitive merger agreement between AMS and PacifiCare. This represents a
significant event in our industry, and I wanted to share some initial thoughts
with you as soon as possible.

         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 approximately $12 billion in revenues, PacifiCare offers
individuals, employers and Medicare beneficiaries a variety of consumer-driven
health care and life insurance products.

         It is our view that this is a compelling strategic business
combination that over time will allow us to increase the value we bring to our
agents and their customers. 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 business - markets where we have long-standing expertise.

|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 can make available to our agents
         and their customers.

         In addition, 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.

         I anticipate that very little will change in your day-to-day
interaction with AMS. Our sales professionals who operate from our regional
offices around the country will still be there to support your sales effort.
The premier customer service you have come to rely on from AMS won't miss a
beat. In fact, every department at AMS that you interact with remains dedicated
to providing you with timely and professional support. Your next call to us
will confirm that.

         As AMS and PacifiCare work to close our transaction by the end of the
year or early next, I have asked our sales representatives to be particularly
diligent in keeping you informed about the merger process.

         In the meantime, I want to assure you that both companies continue to
respect the basic tenet of our industry: Our success in our business is
directly linked to how well we help you succeed in yours. We remain committed
to that. Sincerely,

/s/ Sam Miller
Samuel V.  Miller
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.