HARRIS ASSOCIATES INVESTMENT TRUST
                        Supplement dated April 23, 2001
                      to Prospectus dated January 26, 2001

                       CLOSING OF THE OAKMARK SELECT FUND

    As of the close of business on May 4, 2001, The Oakmark Select Fund (the
"Fund") will close to purchases by new investors, except as described below. The
Fund is taking this step to facilitate the portfolio managers' ability to manage
the Fund effectively.

    IF YOU ARE CURRENTLY A SHAREHOLDER IN THE FUND (IN YOUR OWN NAME OR AS A
BENEFICIAL OWNER OF SHARES HELD IN SOMEONE ELSE'S NAME), YOU MAY CONTINUE TO
MAKE ADDITIONAL INVESTMENTS IN THE FUND AND REINVEST YOUR DIVIDENDS AND CAPITAL
GAINS DISTRIBUTIONS.

    YOU MAY OPEN A NEW ACCOUNT, EVEN THOUGH THE FUND IS CLOSED, IF:

    - You purchase through an employee retirement plan whose records are
      maintained by a trust company or plan administrator and whose investment
      alternatives include shares of the Fund;

    - You are transferring or "rolling over" into an IRA account of the Fund
      from an employee benefit plan through which you held shares of the Fund
      (if your plan doesn't qualify for rollovers, you may still open a new
      account with all or part of the proceeds of a distribution from the plan);

    - You purchase into an annuity account offered by a company that includes
      shares of the Fund as an investment alternative for such account; or

    - Your investment in the Fund, in the judgment of Harris Associates L.P.
      ("HALP"), would not adversely affect HALP's ability to manage the Fund
      effectively.

    The board of trustees of the Trust concluded that permitting the additional
investments described above would not adversely affect the ability of HALP to
manage the Fund effectively. The Trust reserves the right to re-open the Fund to
new investors or to modify the extent to which future sales of shares are
limited.

    If you have any questions about your eligibility to purchase shares of the
Fund, please call 1-800-OAKMARK or visit The Oakmark Family of Funds' website at
www.oakmark.com.

SELSUPP401