GATX CORP — Director's Dealing 2007

May 18, 2007

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: GATX CORP (GMT)
CIK: 0000040211
Period of Report: 2007-05-16

Reporting Person: DUDDY GAIL L (N/A)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2007-05-16	Common Stock	M	6000	$33.4688	Acquired	20275	Direct
2007-05-16	Common Stock	M	1850	$39.145	Acquired	22125	Direct
2007-05-16	Common Stock	M	9100	$30.4688	Acquired	31225	Direct
2007-05-16	Common Stock	S	22550	$50.5	Disposed	8675	Direct
2007-05-17	Common Stock	M	8150	$39.145	Acquired	16825	Direct
2007-05-17	Common Stock	M	3900	$30.4688	Acquired	20725	Direct
2007-05-17	Common Stock	M	8750	$31.735	Acquired	29475	Direct
2007-05-17	Common Stock	S	20800	$50.5	Disposed	8675	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2007-05-16	1997 NQ Stock Option (Right to Buy)	$33.4688	M	6000	Disposed	2007-10-24	Common Stock (6000)	Direct
2007-05-16	2001 NQ Stock Option (Right to Buy)	$39.145	M	1850	Disposed	2011-07-27	Common Stock (1850)	Direct
2007-05-16	2000 NQ Stock Option (Right to Buy)	$30.4688	M	9100	Disposed	2010-03-10	Common Stock (9100)	Direct
2007-05-17	2001 NQ Stock Option (Right to Buy)	$39.145	M	8150	Disposed	2011-07-27	Common Stock (8150)	Direct
2007-05-17	2000 NQ Stock Option (Right to Buy)	$30.4688	M	3900	Disposed	2010-03-10	Common Stock (3900)	Direct
2007-05-17	2002 NQ Stock Option (Right to Buy)	$31.735	M	8750	Disposed	2012-04-26	Common Stock (8750)	Direct

Footnotes

F1: 50% of option granted may be exercised commencing 1 year from the date of the grant, an additional 25% commencing 2 years from the date of the grant and the remaining 25% commencing 3 years from the date of the grant.

F2: 50% of option granted may be exercised commencing 1 year from the date of the grant, an additional 25% commencing 2 years from the date of the grant and the remaining 25% commencing 3 years from the date of the grant.

F3: 50% of option granted may be exercised commencing 1 year from the date of the grant, an additional 25% commencing 2 years from the date of the grant and the remaining 25% commencing 3 years from the date of the grant.

F4: 50% of option granted may be exercised commencing 1 year from the date of the grant, an additional 25% commencing 2 years from the date of the grant and the remaining 25% commencing 3 years from the date of the grant.

F5: 50% of option granted may be exercised commencing 1 year from the date of the grant, an additional 25% commencing 2 years from the date of the grant and the remaining 25% commencing 3 years from the date of the grant.