**Exhibit 4.3.2**

** **

**AMENDMENT NO. 2**

** **

**TO**

 

**INVESTOREQUITYHOLDERS AGREEMENT**

** **

AMENDMENT (this “***Amendment***”), dated as of March 12,2009, to the INVESTOR EQUITYHOLDERS AGREEMENT (as previously amended and amendedhereby, the “***Agreement***”),dated as of February 10, 2005, among Emergency Medical Services L.P., aDelaware limited partnership (the “***Company***”), Onex Partners LP, a Delawarelimited partnership (“***OnexPartners***”), equityholders signatory thereto and such otherequityholders of the Company as may, from time to time, become parties to theAgreement in accordance with the provisions thereof.  Any capitalized term used herein and notdefined shall have the meaning given to such term in the Agreement.

 

Pursuant to Section 8.11 of the Agreement, theCompany, the Majority Onex Investors and Other Investors holding a majority ofthe Units held by all Other Investors desire to amend the Agreement as setforth herein.

 

The parties agree hereby as follows:

 

1.             Amendments.

 

(a)           The definition of “***Pre-QPO Units***” ishereby amended to read in its entirety as follows:

 

The term “***Pre-QPOUnits***” means, as to any Person, the Units held by that Personimmediately prior to the consummation of a Qualified Public Offering, andincluding any Units issued or issuable upon the exercise of any option held bythat Person immediately prior to the consummation of a Qualified PublicOffering.

 

2.             Governing Law.  This Amendment shall be governed by, andinterpreted in accordance with, the laws of the State of Delaware.

 

3.             Counterparts.  This Amendment may be executed in any numberof counterparts which together shall constitute one and the same instrument.

 

4.             No FurtherAmendment.  Except asexpressly amended in paragraph 1 of this Amendment, the terms and conditions ofthe Agreement shall remain in full force and effect, and are hereby ratifiedand confirmed in all respects.

 

*  *  *

 

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**IN WITNESS WHEREOF**, the parties have causedthis Amendment to be executed by their respective officers thereunto dulyauthorized, as of the date first above written.

 
| EMERGENCY  MEDICAL SERVICES CORPORATION, |                                                     |
|------------------------------------------|----------------------------------------------------------|
| as  successor to the issuer of the Units |                                                     |
|                                     |                                                     |
|                                     |                                                     |
| By:                                      | /s/  Todd G. Zimmerman                                   |   |
|                                     | Name:   Todd G. Zimmerman                      |   |
|                                     | Title:      Executive Vice President |   |
|                                     |                                                     |
| EMERGENCY  MEDICAL SERVICES L.P.         |                                                     |
|                                     |                                                     |
| By:                                      | Emergency  Medical Services                              |   |
|                                     | Corporation,its  general partner                         |   |
|                                     |                                                     |   |
|                                     |                                                     |   |
| By:                                      | /s/  Todd G. Zimmerman                                   |   |
|                                     | Name:    Todd G. Zimmerman                     |   |
|                                     | Title:      Executive Vice President |   |
|                                     |                                                     |   |
|                                     |                                                     |   |
| OTHER  INVESTORS:                        |                                                     |
|                                     |                                                     |   |
|                                     |                                                     |   |
|                                     | /s/  William A. Sanger                                   |   |
|                                     | William  A. Sanger                                       |   |

 

 
| ONEX  PARTNERS LP (as a Majority Onex Investor) |                                                | ONEX  PARTNERS LLC (as a Majority Onex Investor) |
|-------------------------------------------------|-----------------------------------------------------|--------------------------------------------------|
|                                            |                                                |                                             |   |
| By:                                             | Onex  Partners GP LP, its General Partner           |                                             | By: | /s/  Robert M. Le Blanc |
| By:                                             | Onex  Partners Manager LP, its Agent                |                                             |   | Name:   Robert M. Le Blanc |
| By:                                             | Onex  Partners Manager GP Inc., its General Partner |                                             |   | Title:      Director |
|                                            |                                                |                                             |   |   |
| By:                                             | /s/  Robert M. Le Blanc                             |                                             | By: | /s/  Donald F. West |
|                                            | Name:   Robert M. Le Blanc                |                                             |   | Name:   Donald F. West |
|                                            | Title:      President           |                                             |   | Title:      Director |
|                                            |                                                |                                             |   |   |
|                                            |                                                |                                             |   |   |
| By:                                             | /s/  Donald F. West                                 |                                             |   |   |
|                                            | Name:   Donald F. West                    |                                             |   |   |
|                                            | Title:      Vice President      |                                             |   |   |

 

[SIGNATURE PAGE TO AMENDMENT NO. 2 TO INVESTOR EQUITYHOLDERS AGREEMENT]

 

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