COLUMBIA ACORN FUND

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
                  Columbia Acorn Fund - Class A, B and C shares

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares" on page 13 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES

Purchases and exchanges should be made for investment purposes only. Frequent
purchases, redemptions or exchanges of Fund shares may disrupt portfolio
management and increase Fund expenses. The Fund has adopted certain policies and
methods intended to identify and to discourage frequent trading in the Fund.
However, as discussed below, the Fund cannot ensure that all such activity can
be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent
trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus accounts, in which shares are held in the name of an intermediary on
behalf of multiple beneficial owners, are a common form of holding shares among
financial intermediaries, retirement plans and variable insurance products. The
Fund typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.



Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 11
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

You may exchange your shares for shares of the same share class of another fund
distributed by Columbia Funds Distributor, Inc. at net asset value. If your
shares are subject to a CDSC, you will not be charged a CDSC upon the exchange.
However, when you sell the shares acquired through the exchange, the shares may
be subject to a CDSC, depending upon when you originally purchased the shares
you are exchanging. For purposes of computing the CDSC, the length of time you
have owned your shares will be computed from the date of your original purchase
and the applicable CDSC will be the CDSC of the original fund. Shareholders of
Columbia Acorn Funds that qualify to purchase Class A shares at net asset value
may exchange their Class A shares for Class Z shares of another fund distributed
by Columbia Funds Distributor, Inc. (see the Statement of Additional Information
for a description of these situations). Unless your account is part of a
tax-deferred retirement plan, an exchange is a taxable event, and you may
realize a gain or a loss for tax purposes. The Fund may terminate your exchange
privilege if the adviser determines that your exchange activity is likely to
adversely impact its ability to manage the Fund. See "Fund Policy on Trading of
Fund Shares" for the Fund's policy. To exchange by telephone, call
1-800-422-3737.



                               COLUMBIA ACORN FUND

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
                      Columbia Acorn Fund - Class Z shares

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares" on page 9 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES

Purchases and exchanges should be made for investment purposes only. Frequent
purchases, redemptions or exchanges of Fund shares may disrupt portfolio
management and increase Fund expenses. The Fund has adopted certain policies and
methods intended to identify and to discourage frequent trading in the Fund.
However, as discussed below, the Fund cannot ensure that all such activity can
be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent
trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus accounts, in which shares are held in the name of an intermediary on
behalf of multiple beneficial owners, are a common form of holding shares among
financial intermediaries, retirement plans and variable insurance products. The
Fund typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.



Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 8
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

You may exchange your shares for Class Z or Class A shares of certain other
funds distributed by Columbia Funds Distributor, Inc., at net asset value.
Unless your account is part of a tax-deferred retirement plan, an exchange is a
taxable event, and you may realize a gain or a loss for tax purposes. The Fund
may terminate your exchange privilege if the adviser determines that your
exchange activity is likely to adversely impact its ability to manage the Fund.
See "Fund Policy on Trading of Fund Shares" for the Fund's policy. To exchange
by telephone, call 1-800-345-6611.



                          COLUMBIA ACORN INTERNATIONAL

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
             Columbia Acorn International - Class A, B and C shares

Effective immediately, the section entitled "PRINCIPAL INVESTMENT RISKS - Market
Timers" on page 3 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

Market timers. Because the Fund invests predominantly in foreign securities, the
Fund may be particularly susceptible to market timers. Market timers generally
attempt to take advantage of the way the Fund prices its shares by trading based
on market information they expect will lead to a change in the Fund's net asset
value on the next pricing day. Market timing activity may be disruptive to Fund
management and, since a market timer's profits are effectively paid directly out
of the Fund's assets, negatively impact the investment returns of other
shareholders. Although the Fund has adopted certain policies and methods
intended to identify and to discourage frequent trading based on this strategy,
it cannot ensure that all such activity can be identified or terminated.

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares" on page 13 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES

Purchases and exchanges should be made for investment purposes only. Frequent
purchases, redemptions or exchanges of Fund shares may disrupt portfolio
management and increase Fund expenses. The Fund has adopted certain policies and
methods intended to identify and to discourage frequent trading in the Fund.
However, as discussed below, the Fund cannot ensure that all such activity can
be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent



trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus accounts, in which shares are held in the name of an intermediary on
behalf of multiple beneficial owners, are a common form of holding shares among
financial intermediaries, retirement plans and variable insurance products. The
Fund typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.

Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 11
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

You may exchange your shares for shares of the same share class of another fund
distributed by Columbia Funds Distributor, Inc. at net asset value. If your
shares are subject to a CDSC, you will not be charged a CDSC upon the exchange.
However, when you sell the shares acquired through the exchange, the shares may
be subject to a CDSC, depending upon when you originally purchased the shares
you are exchanging. For purposes of computing the CDSC, the length of time you
have owned your shares will be computed from the date of your original purchase
and the applicable CDSC will be the CDSC of the original fund. Shareholders of
Columbia Acorn Funds that qualify to purchase Class A shares at net asset value
may exchange their Class A shares for Class Z shares of another fund distributed
by Columbia Funds Distributor, Inc. (see the Statement of Additional Information
for a description of these situations). Unless your account is part of a
tax-deferred retirement plan, an exchange is a taxable event, and you may
realize a gain or a loss for tax purposes. The Fund may terminate your exchange
privilege if the adviser determines that your exchange activity is likely to
adversely impact its ability to manage the Fund. See "Fund Policy on Trading of
Fund Shares" for the Fund's policy. If you acquired Class A shares of Columbia
Acorn International by exchange from another fund, you will not be permitted to
exchange those shares into another fund for 30 days, although you may redeem
those shares at any time. An exchange order received prior to the expiration of
the 30-day period will not be honored. To exchange by telephone, call
1-800-422-3737.



                          COLUMBIA ACORN INTERNATIONAL

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
                  Columbia Acorn International - Class Z shares

Effective immediately, the section entitled "PRINCIPAL INVESTMENT RISKS - Market
Timers" on page 3 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

Market timers. Because the Fund invests predominantly in foreign securities, the
Fund may be particularly susceptible to market timers. Market timers generally
attempt to take advantage of the way the Fund prices its shares by trading based
on market information they expect will lead to a change in the Fund's net asset
value on the next pricing day. Market timing activity may be disruptive to Fund
management and, since a market timer's profits are effectively paid directly out
of the Fund's assets, negatively impact the investment returns of other
shareholders. Although the Fund has adopted certain policies and methods
intended to identify and to discourage frequent trading based on this strategy,
it cannot ensure that all such activity can be identified or terminated.

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares and Redemption Fees" on page 11 of the Fund's prospectus is deleted in
its entirety and replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES AND REDEMPTION FEES

Purchases and exchanges should be made for investment purposes only. Frequent
purchases, redemptions or exchanges of Fund shares may disrupt portfolio
management and increase Fund expenses. The Fund has adopted certain policies and
methods intended to identify and to discourage frequent trading in the Fund.
However, as discussed below, the Fund cannot ensure that all such activity can
be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent
trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus



accounts, in which shares are held in the name of an intermediary on behalf of
multiple beneficial owners, are a common form of holding shares among financial
intermediaries, retirement plans and variable insurance products. The Fund
typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.

Redemption Fee. In addition, if you redeem or exchange shares of the Fund that
you have owned 60 days or less, the Fund will charge you a redemption fee of 2%
of the redemption proceeds. The Fund will use the "first-in" "first-out" method
to determine when shares were purchased. Shares purchased prior to February 10,
2003 will not be subject to the redemption fee. The redemption fee will be
deducted from your redemption proceeds and retained by the Fund to help cover
transaction and tax costs that long-term investors may bear when the Fund
realizes capital gains as a result of selling securities to meet investor
redemptions. The redemption fee is not imposed on redemptions of shares
purchased through reinvestment of dividends and distributions, or exchanges of
shares for Class Z shares of a fund distributed by Columbia Funds Distributor,
Inc. that has a redemption fee. The Fund may waive the 2% redemption fee for
401(k) plans that are in the process of liquidating their Fund investments.

Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 9
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

Generally, you may exchange your Class Z or Class A shares of the Fund for
shares of another fund at no additional charge. However, if you exchange Class Z
shares of Columbia Acorn International that you have owned 60 days or less for
Class Z shares of a fund distributed by Columbia Funds Distributor, Inc. that
does not have a redemption fee (including Columbia Acorn Fund, Columbia Acorn
USA and Columbia Acorn Select), the Fund will charge you a redemption fee of 2%
of the redemption proceeds. Exchanges between Columbia Acorn International and
Columbia Acorn International Select (or a fund distributed by Columbia Funds
Distributor, Inc. that has a redemption fee) will not be subject to the 2%
redemption fee. You also may exchange your Class Z shares of any Fund for Class
Z shares or, if there are no Class Z shares, Class A shares of certain other
funds distributed by Columbia Funds Distributor, Inc., at net asset value
without a sales charge. Unless your account is part of a tax-deferred retirement
plan, an exchange is a taxable event, and you may realize a gain or a loss for
tax purposes. The Funds may terminate your exchange privilege if the adviser
determines that your exchange activity is likely to adversely impact its



ability to manage the Funds. See "Fund Policy on Trading of Fund Shares and
Redemption Fees" for the Fund's policy. To exchange by telephone, call
1-800-345-6611.



                               COLUMBIA ACORN USA

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
                  Columbia Acorn USA - Class A, B and C shares

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares" on page 13 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES

Purchases and exchanges should be made for investment purposes only. Frequent
purchases, redemptions or exchanges of Fund shares may disrupt portfolio
management and increase Fund expenses. The Fund has adopted certain policies and
methods intended to identify and to discourage frequent trading in the Fund.
However, as discussed below, the Fund cannot ensure that all such activity can
be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent
trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus accounts, in which shares are held in the name of an intermediary on
behalf of multiple beneficial owners, are a common form of holding shares among
financial intermediaries, retirement plans and variable insurance products. The
Fund typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.



Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 11
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

You may exchange your shares for shares of the same share class of another fund
distributed by Columbia Funds Distributor, Inc. at net asset value. If your
shares are subject to a CDSC, you will not be charged a CDSC upon the exchange.
However, when you sell the shares acquired through the exchange, the shares may
be subject to a CDSC, depending upon when you originally purchased the shares
you are exchanging. For purposes of computing the CDSC, the length of time you
have owned your shares will be computed from the date of your original purchase
and the applicable CDSC will be the CDSC of the original fund. Shareholders of
Columbia Acorn Funds that qualify to purchase Class A shares at net asset value
may exchange their Class A shares for Class Z shares of another fund distributed
by Columbia Funds Distributor, Inc. (see the Statement of Additional Information
for a description of these situations). Unless your account is part of a
tax-deferred retirement plan, an exchange is a taxable event, and you may
realize a gain or a loss for tax purposes. The Fund may terminate your exchange
privilege if the adviser determines that your exchange activity is likely to
adversely impact its ability to manage the Fund. See "Fund Policy on Trading of
Fund Shares" for the Fund's policy. To exchange by telephone, call
1-800-422-3737.



                               COLUMBIA ACORN USA

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
                       Columbia Acorn USA - Class Z shares

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares" on page 10 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES

Purchases and exchanges should be made for investment purposes only. Frequent
purchases, redemptions or exchanges of Fund shares may disrupt portfolio
management and increase Fund expenses. The Fund has adopted certain policies and
methods intended to identify and to discourage frequent trading in the Fund.
However, as discussed below, the Fund cannot ensure that all such activity can
be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent
trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus accounts, in which shares are held in the name of an intermediary on
behalf of multiple beneficial owners, are a common form of holding shares among
financial intermediaries, retirement plans and variable insurance products. The
Fund typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.



Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 8
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

You may exchange your shares for Class Z or Class A shares of certain other
funds distributed by Columbia Funds Distributor, Inc., at net asset value.
Unless your account is part of a tax-deferred retirement plan, an exchange is a
taxable event, and you may realize a gain or a loss for tax purposes. The Fund
may terminate your exchange privilege if the adviser determines that your
exchange activity is likely to adversely impact its ability to manage the Fund.
See "Fund Policy on Trading of Fund Shares" for the Fund's policy. To exchange
by telephone, call 1-800-345-6611.



                       COLUMBIA ACORN INTERNATIONAL SELECT

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
          Columbia Acorn International Select - Class A, B and C shares

Effective immediately, the section entitled "PRINCIPAL INVESTMENT RISKS - Market
Timers" on page 3 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

Market timers. Because the Fund invests predominantly in foreign securities, the
Fund may be particularly susceptible to market timers. Market timers generally
attempt to take advantage of the way the Fund prices its shares by trading based
on market information they expect will lead to a change in the Fund's net asset
value on the next pricing day. Market timing activity may be disruptive to Fund
management and, since a market timer's profits are effectively paid directly out
of the Fund's assets, negatively impact the investment returns of other
shareholders. Although the Fund has adopted certain policies and methods
intended to identify and to discourage frequent trading based on this strategy,
it cannot ensure that all such activity can be identified or terminated.

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares" on page 14 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES

Purchases and exchanges should be made for investment purposes only. Frequent
purchases, redemptions or exchanges of Fund shares may disrupt portfolio
management and increase Fund expenses. The Fund has adopted certain policies and
methods intended to identify and to discourage frequent trading in the Fund.
However, as discussed below, the Fund cannot ensure that all such activity can
be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent



trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus accounts, in which shares are held in the name of an intermediary on
behalf of multiple beneficial owners, are a common form of holding shares among
financial intermediaries, retirement plans and variable insurance products. The
Fund typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.

Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 12
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

You may exchange your shares for shares of the same share class of another fund
distributed by Columbia Funds Distributor, Inc. at net asset value. If your
shares are subject to a CDSC, you will not be charged a CDSC upon the exchange.
However, when you sell the shares acquired through the exchange, the shares may
be subject to a CDSC, depending upon when you originally purchased the shares
you are exchanging. For purposes of computing the CDSC, the length of time you
have owned your shares will be computed from the date of your original purchase
and the applicable CDSC will be the CDSC of the original fund. Shareholders of
Columbia Acorn Funds that qualify to purchase Class A shares at net asset value
may exchange their Class A shares for Class Z shares of another fund distributed
by Columbia Funds Distributor, Inc. (see the Statement of Additional Information
for a description of these situations). Unless your account is part of a
tax-deferred retirement plan, an exchange is a taxable event, and you may
realize a gain or a loss for tax purposes. The Fund may terminate your exchange
privilege if the adviser determines that your exchange activity is likely to
adversely impact its ability to manage the Fund. See "Fund Policy on Trading of
Fund Shares" for the Fund's policy. If you acquired Class A shares of Columbia
Acorn International Select by exchange from another fund, you will not be
permitted to exchange those shares into another fund for 30 days, although you
may redeem those shares at any time. An exchange order received prior to the
expiration of the 30-day period will not be honored. To exchange by telephone,
call 1-800-422-3737.



                       COLUMBIA ACORN INTERNATIONAL SELECT

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
              Columbia Acorn International Select - Class Z shares

Effective immediately, the section entitled "PRINCIPAL INVESTMENT RISKS - Market
Timers" on page 3 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

Market timers. Because the Fund invests predominantly in foreign securities, the
Fund may be particularly susceptible to market timers. Market timers generally
attempt to take advantage of the way the Fund prices its shares by trading based
on market information they expect will lead to a change in the Fund's net asset
value on the next pricing day. Market timing activity may be disruptive to Fund
management and, since a market timer's profits are effectively paid directly out
of the Fund's assets, negatively impact the investment returns of other
shareholders. Although the Fund has adopted certain policies and methods
intended to identify and to discourage frequent trading based on this strategy,
it cannot ensure that all such activity can be identified or terminated.

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares and Redemption Fees" on page 10 of the Fund's prospectus is deleted in
its entirety and replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES AND REDEMPTION FEES

Purchases and exchanges should be made for investment purposes only.
Frequent purchases, redemptions or exchanges of Fund shares may disrupt
portfolio management and increase Fund expenses. The Fund has adopted certain
policies and methods intended to identify and to discourage frequent trading in
the Fund. However, as discussed below, the Fund cannot ensure that all such
activity can be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent
trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus



accounts, in which shares are held in the name of an intermediary on
behalf of multiple beneficial owners, are a common form of holding shares among
financial intermediaries, retirement plans and variable insurance products. The
Fund typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.

Redemption Fee. In addition, if you redeem or exchange shares of the Fund that
you have owned 60 days or less, the Fund will charge you a redemption fee of 2%
of the redemption proceeds. The Fund will use the "first-in" "first-out" method
to determine when shares were purchased. Shares purchased prior to February 10,
2003 will not be subject to the redemption fee. The redemption fee will be
deducted from your redemption proceeds and retained by the Fund to help cover
transaction and tax costs that long-term investors may bear when the Fund
realizes capital gains as a result of selling securities to meet investor
redemptions. The redemption fee is not imposed on redemptions of shares
purchased through reinvestment of dividends and distributions, or exchanges of
shares for Class Z shares of a fund distributed by Columbia Funds Distributor,
Inc. that has a redemption fee. The Fund may waive the 2% redemption fee for
401(k) plans that are in the process of liquidating their Fund investments.

Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 9
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

Generally, you may exchange your Class Z or Class A shares of the Funds for
shares of another Fund at no additional charge. However, if you exchange Class Z
shares of Columbia Acorn International Select that you have owned 60 days or
less for Class Z shares of a fund distributed by Columbia Funds Distributor,
Inc. that does not have a redemption fee (including Columbia Acorn Fund,
Columbia Acorn USA and Columbia Acorn Select), the Fund will charge you a
redemption fee of 2% of the redemption proceeds. Exchanges between Columbia
Acorn International and Columbia Acorn International Select (or a fund
distributed by Columbia Funds Distributor, Inc. that has a redemption fee) will
not be subject to the 2% redemption fee. You also may exchange your Class Z
shares of any Fund for Class Z shares, or, if there are no Class Z shares, Class
A shares of certain other funds distributed by Columbia Funds Distributor, Inc.,
at net asset value without a sales charge. Unless your account is part of a
tax-deferred retirement plan, an exchange is a taxable event, and you may
realize a gain or a loss for tax purposes. The Funds may terminate your exchange
privilege if the advisor determines that your exchange activity is likely to
adversely impact its



ability to manage the Funds. See "Fund Policy on Trading of Fund Shares and
Redemption Fees" for the Fund's policy. To exchange by telephone, call
1-800-345-6611.




                              COLUMBIA ACORN SELECT

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
                 Columbia Acorn Select - Class A, B and C shares

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares" on page 12 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES

Purchases and exchanges should be made for investment purposes only. Frequent
purchases, redemptions or exchanges of Fund shares may disrupt portfolio
management and increase Fund expenses. The Fund has adopted certain policies and
methods intended to identify and to discourage frequent trading in the Fund.
However, as discussed below, the Fund cannot ensure that all such activity can
be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent
trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus accounts, in which shares are held in the name of an intermediary on
behalf of multiple beneficial owners, are a common form of holding shares among
financial intermediaries, retirement plans and variable insurance products. The
fund typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.



Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 11
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

You may exchange your shares for shares of the same share class of another fund
distributed by Columbia Funds Distributor, Inc. at net asset value. If your
shares are subject to a CDSC, you will not be charged a CDSC upon the exchange.
However, when you sell the shares acquired through the exchange, the shares may
be subject to a CDSC, depending upon when you originally purchased the shares
you are exchanging. For purposes of computing the CDSC, the length of time you
have owned your shares will be computed from the date of your original purchase
and the applicable CDSC will be the CDSC of the original fund. Shareholders of
Columbia Acorn Funds that qualify to purchase Class A shares at net asset value
may exchange their Class A shares for Class Z shares of another fund distributed
by Columbia Funds Distributor, Inc. (see the Statement of Additional Information
for a description of these situations). Unless your account is part of a
tax-deferred retirement plan, an exchange is a taxable event, and you may
realize a gain or a loss for tax purposes. The Fund may terminate your exchange
privilege if the adviser determines that your exchange activity is likely to
adversely impact its ability to manage the Fund. See "Fund Policy on Trading of
Fund Shares" for the Fund's policy. To exchange by telephone, call
1-800-422-3737.




                              COLUMBIA ACORN SELECT

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
                     Columbia Acorn Select - Class Z shares

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares" on page 10 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES

Purchases and exchanges should be made for investment purposes only. Frequent
purchases, redemptions or exchanges of Fund shares may disrupt portfolio
management and increase Fund expenses. The Fund has adopted certain policies and
methods intended to identify and to discourage frequent trading in the Fund.
However, as discussed below, the Fund cannot ensure that all such activity can
be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent
trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus accounts, in which shares are held in the name of an intermediary on
behalf of multiple beneficial owners, are a common form of holding shares among
financial intermediaries, retirement plans and variable insurance products. The
Fund typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.



Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 9
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

You may exchange your shares for Class Z or Class A shares of certain other
funds distributed by Columbia Funds Distributor, Inc., at net asset value.
Unless your account is part of a tax-deferred retirement plan, an exchange is a
taxable event, and you may realize a gain or a loss for tax purposes. The Fund
may terminate your exchange privilege if the adviser determines that your
exchange activity is likely to adversely impact its ability to manage the Fund.
See "Fund Policy on Trading of Fund Shares" for the Fund's policy. To exchange
by telephone, call 1-800-345-6611.



                            COLUMBIA THERMOSTAT FUND

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
               Columbia Thermostat Fund - Class A, B and C shares

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares" on page 20 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES

Purchases and exchanges should be made for investment purposes only. Frequent
purchases, redemptions or exchanges of Fund shares may disrupt portfolio
management and increase Fund expenses. The Fund has adopted certain policies and
methods intended to identify and to discourage frequent trading in the Fund.
However, as discussed below, the Fund cannot ensure that all such activity can
be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent
trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus accounts, in which shares are held in the name of an intermediary on
behalf of multiple beneficial owners, are a common form of holding shares among
financial intermediaries, retirement plans and variable insurance products. The
Fund typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.



Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 18
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

You may exchange your shares for shares of the same share class of another fund
distributed by Columbia Funds Distributor, Inc. at net asset value. If your
shares are subject to a CDSC, you will not be charged a CDSC upon the exchange.
However, when you sell the shares acquired through the exchange, the shares may
be subject to a CDSC, depending upon when you originally purchased the shares
you are exchanging. For purposes of computing the CDSC, the length of time you
have owned your shares will be computed from the date of your original purchase
and the applicable CDSC will be the CDSC of the original fund. Shareholders of
Columbia Acorn Funds that qualify to purchase Class A shares at net asset value
may exchange their Class A shares for Class Z shares of another fund distributed
by Columbia Funds Distributor, Inc. (see the Statement of Additional Information
for a description of these situations). Unless your account is part of a
tax-deferred retirement plan, an exchange is a taxable event, and you may
realize a gain or a loss for tax purposes. The Fund may terminate your exchange
privilege if the adviser determines that your exchange activity is likely to
adversely impact its ability to manage the Fund. See "Fund Policy on Trading of
Fund Shares" for the Fund's policy. To exchange by telephone, call
1-800-422-3737.



                            COLUMBIA THERMOSTAT FUND

                         Supplement dated March 16, 2004
                       to Prospectus dated May 1, 2003 of
                    Columbia Thermostat Fund - Class Z shares

Effective immediately, the section entitled "Fund Policy on Trading of Fund
Shares" on page 16 of the Fund's prospectus is deleted in its entirety and
replaced with the following:

FUND POLICY ON TRADING OF FUND SHARES

Purchases and exchanges should be made for investment purposes only. Frequent
purchases, redemptions or exchanges of Fund shares may disrupt portfolio
management and increase Fund expenses. The Fund has adopted certain policies and
methods intended to identify and to discourage frequent trading in the Fund.
However, as discussed below, the Fund cannot ensure that all such activity can
be identified or terminated.

Right to Reject or Restrict Orders and Close Accounts. The Fund reserves the
right to restrict, reject or cancel, without any prior notice, any purchase or
exchange order, including transactions accepted by any shareholder's financial
intermediary, when the Fund believes it is in its shareholders best interest. In
the event that the Fund rejects or cancels an exchange request, neither the
redemption nor the purchase side of the exchange will be processed. The Fund may
also fully redeem the shares and close the account of any shareholder whom it
believes is engaged or intends to engage in frequent trading.

Limitations on the Ability to Identify or to Terminate Frequent Trading. There
is no guarantee that the Fund or its agents will be able to detect frequent
trading activity or the shareholders engaged in such activity, or, if it is
detected, to prevent its recurrence. In particular, a substantial portion of
purchase, redemption and exchange orders are received from omnibus accounts.
Omnibus accounts, in which shares are held in the name of an intermediary on
behalf of multiple beneficial owners, are a common form of holding shares among
financial intermediaries, retirement plans and variable insurance products. The
Fund typically is not able to identify trading by a particular beneficial owner,
which may make it difficult or impossible to determine if a particular account
is engaged in frequent trading. There are also operational and technological
limitations on the Fund's agents' ability to identify or terminate frequent
trading activity, and the techniques used by the Fund and its agents are not
anticipated to identify all frequent trading.



Effective immediately, the section entitled "HOW TO EXCHANGE SHARES" on page 15
of the prospectus is deleted in its entirety and replaced with the following:

HOW TO EXCHANGE SHARES

You may exchange your shares for Class Z or Class A shares of certain other
funds distributed by Columbia Funds Distributor, Inc., at net asset value.
Unless your account is part of a tax-deferred retirement plan, an exchange is a
taxable event, and you may realize a gain or a loss for tax purposes. The Fund
may terminate your exchange privilege if the adviser determines that your
exchange activity is likely to adversely impact its ability to manage the Fund.
See "Fund Policy on Trading of Fund Shares" for the Fund's policy. To exchange
by telephone, call 1-800-345-6611.