EXHIBIT 21

                         SUBSIDIARIES OF THE REGISTRANT

     The following is a list of subsidiaries included in GATX's consolidated
financial statements (excluding a number of subsidiaries which would not
constitute a significant subsidiary), and the state of incorporation of each:

<Table>
<Caption>
COMPANY NAME                                                  STATE OF INCORPORATION
- ------------                                                  ----------------------
                                                           
3140172 Canada, Inc. .......................................                  Canada
American Steamship Company..................................                New York
GATX Beteiligungs GmbH......................................                 Germany
GATX Financial Corporation..................................                Delaware
GATX Rail Locomotive Group, LLC.............................                Delaware
GATX Spanish Holding Corporation, S.L. .....................                   Spain
GATX Terminals Overseas Holding Corporation.................                Delaware
GATX Third Aircraft Corporation.............................                Delaware
KVG Kesselwagen Vermietgesellschaft mbH.....................                 Austria
KVG Kesselwagen Vermietgesellschaft GmbH....................                 Germany
O'Farrell Leasing (Holdings) Limited........................          Cayman Islands
O'Farrell Leasing Limited...................................          Cayman Islands
</Table>

     In addition to the above-named subsidiaries, GATX Financial Corporation
includes 53 domestic subsidiaries, 40 foreign subsidiaries, and interests in 31
domestic affiliates and 69 foreign affiliates.

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