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
- ------------                                                   ----------------------
                                                            
GATX Financial Corporation..................................   Delaware
  GATX Technology Services Corporation......................   Delaware
  GATX Third Aircraft Corporation...........................   Delaware
GATX Rail Holding I, Inc....................................   Delaware
</Table>

     In addition to the above named subsidiaries, GATX Financial Corporation
includes 59 domestic subsidiaries, 43 foreign subsidiaries, and interests in 33
domestic affiliates and 55 foreign affiliates.

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