Exhibit 99.CODE

                       Allmerica Investment Trust ("AIT")
                       Allmerica Securities Trust ("AST")
                          Opus Investment Trust ("OIT")

                        FINANCIAL OFFICER CODE OF ETHICS

I.   Introduction

The reputation and integrity of AIT, AST and OIT (the "Funds") are valuable
assets that are vital to the Funds' success. The Funds' senior financial
officers ("SFOs") are responsible for conducting the Funds' business in a manner
that demonstrates a commitment to the highest standards of integrity. The Funds'
SFOs include the principal executive officer, the principal financial officer,
comptroller or principal accounting officer, and any person who performs a
similar function.

The Sarbanes-Oxley Act of 2002 (the "Act") effected sweeping corporate
disclosure and financial reporting reform on public companies, including mutual
funds, to address corporate malfeasance and assure investors that the companies
in which they invest are accurately and completely disclosing financial
information. Under the Act, all public companies (including the Funds) must
either have a code of ethics for their SFOs, or disclose why they do not. The
Act was intended to foster corporate environments which encourage employees to
question and report unethical and potentially illegal business practices. The
Funds have chosen to adopt this Financial Officer Code of Ethics (the "Code") to
encourage its SFOs to act in a manner consistent with the highest principles of
ethical conduct.

II.  Purposes of the Code

The purposes of this Code are:

     .    To promote honest and ethical conduct by the Funds' SFOs, including
          the ethical handling of actual or apparent conflicts of interest
          between personal and professional relationships;

     .    To assist the Funds' SFOs in recognizing and avoiding conflicts of
          interest, including disclosing to an appropriate person any material
          transaction or relationship that reasonably could be expected to give
          rise to such a conflict;

     .    To promote full, fair, accurate, timely, and understandable disclosure
          in reports and documents that the Funds file with, or submit to, the
          SEC and in other public communications the Funds make;

..    To promote Fund compliance with applicable laws, rules and regulations;

..    To encourage the prompt internal reporting to an appropriate person of
     violations of this Code; and

..    To establish accountability for adherence to this Code.

III. Questions about this Code

The Funds' Boards of Trustees have designated Donald Wayman to serve as
Compliance Officer for the implementation and administration of the Code.
Questions about this Code should be directed to the Compliance Officer.

IV.  Conduct Guidelines

The Funds have adopted the following guidelines under which the Funds' SFOs must
perform their official duties and conduct the business affairs of the Funds.

     1.   Ethical and honest conduct of paramount importance. The Funds' SFOs
          must act with honesty and integrity and avoid violations of this Code,
          including the avoidance of actual or apparent conflicts of interest
          with the Funds in personal and professional relationships.




     2.   SFOs must disclose material transactions or relationships. The Funds'
          SFOs must disclose to the Compliance Officer any actual or apparent
          conflicts of interest the SFO may have with the Funds that reasonably
          could be expected to give rise to any violations of this Code. Such
          conflicts of interest may arise as a result of material transactions
          or business or personal relationships to which the SFO may be a party.
          If it is not possible to disclose the matter to the Compliance
          Officer, it should be disclosed to the Funds' Chief Financial Officer,
          Chief Executive Officer or another appropriate person. In addition to
          disclosing any actual or apparent conflicts of interest in which an
          SFO is personally involved, the Funds' SFOs have an obligation to
          report any actual or apparent conflicts which they discover or of
          which they otherwise become aware.

     3.   Standards for quality of information shared with Fund service
          providers. The Funds' SFOs must at all times seek to provide
          information to the Funds' service providers (adviser, administrator,
          outside auditor, outside counsel, custodian, etc.) that is accurate,
          complete, objective, relevant, timely and understandable.

     4.   Standards for quality of information included in periodic reports. The
          Funds' SFOs must at all times endeavor to ensure full, fair, timely,
          accurate, and understandable disclosure in the Funds' periodic
          reports.

     5.   Compliance with laws. The Funds' SFOs must comply with the federal
          securities laws and other laws and rules applicable to the Funds, such
          as the Internal Revenue Code.

     6.   Standard of care. The Funds' SFOs must at all times act in good faith
          and with due care, competence and diligence, without misrepresenting
          material facts or allowing their independent judgment to be
          subordinated. The Funds' SFOs must conduct the affairs of the Funds in
          a responsible manner, consistent with this Code.

     7.   Confidentiality of information. The Funds' SFO's must respect and
          protect the confidentiality of information acquired in the course of
          their professional duties, except when authorized by the applicable
          Fund to disclose it or where disclosure is otherwise legally mandated.
          A SFO may not use confidential information acquired in the course of
          his/her work for personal advantage.

     8.   Sharing of information and educational standards. The Funds' SFOs
          should share information with relevant parties to keep them informed
          of the business affairs of the Funds, as appropriate, and maintain
          skills important and relevant to the Funds' needs.

     9.   Promote ethical conduct. The Funds' SFOs should at all times
          proactively promote ethical behavior among peers in their work
          environment.

     10.  Standards for recordkeeping. The Funds' SFOs must at all times
          endeavor to ensure that the Funds' books and records are thoroughly
          and accurately maintained to the best of their knowledge in a manner
          consistent with applicable laws and this Code.

V.   Waivers of this Code

A SFO may request a waiver of a provision of this Code by submitting his/her
request in writing to the Compliance Officer for appropriate review. For
example, if a family member works for a service provider that prepares the
Funds' financial statements, a SFO may have a potential conflict of interest in
reviewing those statements and should seek a waiver of this Code to review the
work. An executive officer of the Funds, or another appropriate person (such as
a designated Board or Audit Committee member), will decide whether to grant a
waiver. All waivers of this code must be disclosed to the Funds' shareholders to
the extent required by SEC rules.

VI.  Annual Certification

The Funds' SFOs will be asked to certify on an annual basis that they are in
full compliance with this Code. To the extent necessary, the Funds' Compliance
Officer will provide guidance on the conduct required by this Code and the
manner in which violations or suspected violations must be reported and waivers
must be requested.




VII. Reporting Violations

In the event that a SFO discovers or, in good faith, suspects a violation of
this Code, the SFO must immediately report the violation or suspected violation
to the Compliance Officer. The Compliance Officer may, in his or her discretion,
consult with another member of Fund senior management or the Board in
determining how to address the suspected violation. For example, a Code
violation may occur when a Fund periodic report or financial statement omits a
material fact, or is technically accurate but, in the view of the SFO, is
written in a way that obscures its meaning.

When the Funds' service providers perform substantially all of the work relating
to the preparation of the Funds' financial statements and administration of the
day-to-day operations of the Funds, the Funds' SFOs should make reasonable
efforts to monitor the conduct of the service providers for actions that may be
illegal, could be viewed as dishonest or unethical, or otherwise inconsistent
with this Code. In the event that an SFO discovers or, in good faith, suspects
that a Fund service provider may have committed such an action, the SFO must
report the action to the Compliance Officer - even if the service provider has
its own code of ethics for its SFOs or employees.

SFOs who report violations or suspected violations in good faith will not be
subject to retaliation of any kind. Reported violations will be investigated and
addressed promptly and will be treated as confidential to the extent possible.

VIII. Violations of the Code

Dishonest or unethical conduct or conduct that is illegal will constitute a
violation of this Code, regardless of whether this Code specifically refers to
such particular conduct. A violation of this Code may result in disciplinary
action, up to and including termination of employment. A variety of laws apply
to the Funds and their operations, including the Securities Act of 1933, the
Investment Company Act of 1940, state laws relating to duties owed by Fund
officers, and criminal laws.

Adopted: August 5, 2003