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                                                                   EXHIBIT 10.11

                        AMENDMENT TO EMPLOYMENT AGREEMENT

                  This Amendment to Employment Agreement (the "Amendment") is
entered into this 20th day of August, 2004 between Laidlaw International, Inc.
("Laidlaw") and Douglas A Carty (the "Executive").

                  WHEREAS, the Executive and Laidlaw, Inc. ("LINC") entered into
an employment agreement dated December 9, 2002 (the "Employment Agreement");

                  WHEREAS, Laidlaw acquired the assets of LINC and assumed the
Employment Agreement; and

                  WHEREAS, the Executive and Laidlaw mutually desire to amend
the Employment Agreement;

                  NOW THEREFORE, the parties hereby agree to amend the
Employment Agreement as follows:

                  1. All references to LINC contained in the Employment
Agreement shall be amended to reference Laidlaw.

                  2. Article 4(b) shall be amended to read as follows:

                  "The Executive will be eligible to participate in Laidlaw's
Short Term Incentive Plan at such target bonus and maximum bonus as shall be
established by the Committee after consultation with the Executive. On the date
of this Agreement, the Executive's target bonus is 75% of Base Salary and the
maximum bonus is 150% of Base Salary. The Executive's right to receive any bonus
under the Short Term Incentive Plan shall be determined based only upon
qualitative measurements established by the Committee after consultation with
the Executive and as set forth in accordance with the Short Term Incentive
Plan."

                  3. Article 4(c) shall be amended to add the following:

                  "All vacation earned must be taken by the end of the calendar
year following accrual or it is forfeited."

                  4. Article 5 shall be amended to read as follows:

                  "Laidlaw will provide the Executive with a monthly allowance
of One Thousand Dollars ($1,000.00) for expenses incurred by the Executive for
an automobile and its related operating expenses. Laidlaw shall also reimburse
the Executive for reasonable gas and insurance expenses as incurred, provided
that the Executive provides to Laidlaw an itemized written account and receipts
acceptable to Laidlaw."

                  5. Article 6(a)(iii) shall be amended to add the following:

                  "In addition, if such termination occurs on or after the
second anniversary of his employment with Laidlaw (and its predecessors), then
Laidlaw shall also pay Executive a

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monthly amount equal to one-twelfth of the Executive's target bonus in effect at
the time of the Executive's termination of employment for a period of 24 months
following such termination."

                  6. Article 11 shall be amended by substituting the following
for Laidlaw's and the Executive's address:

                  Laidlaw International, Inc.
                  55 Shuman Boulevard, Suite 400
                  Naperville, IL 60563
                  Attention: General Counsel

                  If to the Executive, at such address as Executive provides to
Laidlaw from time to time as part of his personnel records, or to such other
names or addresses as Laidlaw or the Executive shall designate by notice to the
other in the manner specified in this paragraph.

                  No other terms of the Employment Agreement shall be modified
by this Amendment and the Employment Agreement shall continue in all other
respects in full force and effect in accordance with its terms.

                  This Amendment to Employment Agreement may be executed in one
or more counterparts, each of which shall be deemed an original but al of which
together will constitute one and the same instrument.

LAIDLAW INTERNATIONAL, INC.                 EXECUTIVE

____________________________________        ____________________________________
By: Beth Byster Corvino                     Douglas A. Carty
Its: Senior Vice President, General
Counsel and Corporate Secretary