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Proc-Type: 2001,MIC-CLEAR
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<SEC-DOCUMENT>0000891804-05-003600.txt : 20051207
<SEC-HEADER>0000891804-05-003600.hdr.sgml : 20051207
<ACCEPTANCE-DATETIME>20051207102954
ACCESSION NUMBER:		0000891804-05-003600
CONFORMED SUBMISSION TYPE:	497
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20051207
DATE AS OF CHANGE:		20051207
EFFECTIVENESS DATE:		20051207

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COLUMBIA ACORN TRUST
		CENTRAL INDEX KEY:			0000002110
		IRS NUMBER:				362692100
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		497
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	002-34223
		FILM NUMBER:		051248668

	BUSINESS ADDRESS:	
		STREET 1:		227 W MONROE STE 3000
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
		BUSINESS PHONE:		3126349200

	MAIL ADDRESS:	
		STREET 1:		227 W MONROE STE 3000
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	LIBERTY ACORN TRUST
		DATE OF NAME CHANGE:	20010424

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ACORN INVESTMENT TRUST
		DATE OF NAME CHANGE:	19940204

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ACORN FUND INC
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>497
<SEQUENCE>1
<FILENAME>file002.txt
<DESCRIPTION>COLUMBIA ACORN TRUST
<TEXT>

                       COLUMBIA ACORN INTERNATIONAL SELECT

                        SUPPLEMENT DATED DECEMBER 7, 2005
     TO PROSPECTUS DATED MAY 1, 2005 OF COLUMBIA ACORN INTERNATIONAL SELECT

         Effective immediately, Chris Olson is the sole portfolio manager of
Columbia Acorn International Select.


</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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