Exhibit 10.14.3

Emergency Medical Services Corporation    2007 Long-Term Incentive Plan    Nonqualified Stock Option Agreement

Nonqualified Stock Option Agreement (the "Agreement") by and between Emergency Medical Services Corporation, a Delaware corporation,
(the "Company") and the undersigned employee of the Company or a subsidiary thereof (the "Optionee").

1.2007 Long-Term Incentive Plan.This Agreement is
entered into pursuant to the terms of the Emergency Medical Services Corporation 2007 Long-Term Incentive Plan, as it may be amended from time to time (the "Plan"), which is incorporated
herein and made a part hereof for all purposes. To the extent that any provision of this Agreement conflicts with the express terms of the Plan, the terms of the Plan shall control and, if necessary,
the applicable provisions of this Agreement shall be deemed amended so as to carry out the purpose and intent of the Plan.

2.Definitions.All capitalized terms used in this Agreement
shall have the meanings ascribed to them in the Plan unless otherwise defined in this Agreement. As used in this Agreement, the following terms have the meanings set forth below:



3.Grant of Option.In order to encourage the Optionee's
contribution to the successful performance of the Company and its subsidiaries, and in consideration of the covenants and promises of the Optionee herein contained, effective as of the date of grant
set forth on the signature page of this Agreement (the "Date of Grant"), the Company hereby grants to the Optionee an option (the "Option") to purchase the number of shares of Class A Common
Stock, par value $0.01 per share, set forth on the signature page hereof (the "Shares"), on the terms and conditions set forth herein and in the Plan.

4.Exercise Price.The purchase price of each Share (the
"Exercise Price") covered by the Option is the Exercise Price set forth on the signature page of this Agreement.

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5.Vesting and Exercisability.Unless the Committee, in its sole
and absolute discretion, elects to accelerate the vesting and/or exercisability of some or all of the Option, the Option shall vest and become exercisable in the following ways:



6.Term of Option.The Option (whether or not then exercisable
in whole or in part) shall terminate automatically on the earliest to occur of:



7.Manner of Exercise of Option.

(a)   The
Optionee may exercise any then exercisable portion of the Option in accordance with the provisions of the Plan.

(b)   The
Company may delay the issuance of Shares covered by the Option as provided in the Plan.

8.Beneficiary Designations.The person designated by the
Optionee as his or her beneficiary(ies) on the signature page hereof (each a "Beneficiary") shall receive any benefit otherwise due the Optionee in the event of the death of the Optionee prior to
receipt of such benefit. The Optionee shall have the right to change the Beneficiary or Beneficiaries from time to time; provided, however, that any change shall not become effective until received in
writing by the Secretary of the Company. If any designated Beneficiary survives the Optionee but dies before receiving all of his benefits hereunder, any remaining benefits due him shall be
distributed to the deceased Beneficiary's estate. If there is no effective Beneficiary designation on file at the time of the Optionee's death, or if the designated Beneficiary or Beneficiaries have
all predeceased such Optionee, the payment of any remaining benefits shall be made to the Optionee's estate.

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9.Limitation of Rights.Nothing in this Agreement or the Plan
shall be construed to:



10.Non-Transferability.    The Option is not
transferable, in whole or in part, except as provided in the Plan. The right of the Optionee to exercise the Option (as and when exercisable) shall not be assignable or transferable by the Optionee
otherwise than by will or the laws of descent and distribution, and the Option may be exercised during the lifetime of the Optionee only by him (or his legal representative in the event that he is
disabled). Any other transfer shall be null and void and without effect, including, without limitation, any purported assignment, whether voluntary or by operation of law, pledge, hypothecation or
other disposition contrary to the provisions hereof, or levy of execution, attachment, trustee process or similar process, whether legal or equitable, upon the Option.

11.Successors and Assigns.This Agreement shall bind and inure
to the benefit of and be enforceable by the Optionee, the Company and their respective permitted successors and assigns (including personal representatives, heirs and legatees), except that the
Optionee may not assign any rights or obligations under this Agreement except to the extent and in the manner expressly permitted herein.

12.Securities Laws.(a) The Company will not be required to
deliver any Shares pursuant to this Agreement if, in the opinion of counsel for the Company, such issuance would violate the Securities Act of 1933 or any other applicable federal or state securities
laws or regulations (the "Securities Act"). If the disposition of the Shares to be issued upon exercise of the Option are not covered by a current registration statement under the Securities Act when
the Option is exercised, the Company may require that the Optionee, prior to the issuance of any such Shares, deliver to the Company a written statement, in form and content acceptable to the Company,
in its sole discretion, stating (i) that the Optionee is purchasing the Shares for investment and not with a view to the sale or distribution thereof, and (ii) that the Optionee will not
sell any Shares of the Company that the Optionee may then own or thereafter acquire except pursuant to a registered offering or a valid exemption from registration. The Company shall place the
following restrictive legend upon any stock certificate issued by reason of such an exercise:



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(b)   The
Company shall be under no obligation to qualify the Shares for sale under any securities laws or to cause a registration statement or a post-effective
amendment to any registration to be prepared for the purposes of covering the issue or sale of Shares.

13.Adjustments upon Changes in Capitalization and Other
Events.(a) In the event of any merger, reorganization, consolidation, recapitalization, stock dividend, stock split, combination, or exchange of shares or other
change in corporate structure affecting any class of common stock of the Company, the Committee shall make such adjustments in the Exercise Price of the Option, and the class and number of shares
subject to the Option, as may be determined to be appropriate by the Committee, and any such adjustment may, in the sole discretion of the Committee, take the form of an Option covering more than one
class of Common Stock. Such adjustment shall be conclusive and binding for all purposes.

(b)   In
connection with a Liquidity Event, and without limiting the provisions of clause Section 5(b)(ii) and 6(d), the Company may, in the sole discretion of the
Board, deliver to the Optionee, to the extent that the right to purchase Shares under the Option has vested and is exercisable, the same kind of consideration (net of the Exercise Price for such
Shares) that is delivered to the shareholders of the Company as a result of such Liquidity Event, or the Board may, in its sole discretion, cancel the Option, to the extent not theretofor exercised,
in exchange for cash consideration in an amount equal to the value of those securities or other consideration the Optionee would have received had the Option been exercised (to the extent it has
vested and is exercisable and has not been exercised), less the Exercise Price therefor. Upon the Optionee's receipt of such consideration, the Option shall immediately terminate and be of no further
force or effect, whether vested or not. The value of the securities or other consideration the Optionee would have received if the Option had been exercised and the value of any consideration
exchanged for an Option shall be determined in good faith by the Board. Without limiting the foregoing, payment of any consideration pursuant to this Section 13(b) may be made in cash to the
Optionee if the Optionee is not an accredited investor within the meaning of Regulation D under the Securities Act of 1933.

(c)   Upon
the dissolution or liquidation of the Company, the Option shall terminate, but the Optionee (if at such time in the employ the Company or any of its subsidiaries)
shall have the right, immediately prior to such dissolution or liquidation, to exercise any portion of the Option that has vested and is exercisable.

14.Withholding Taxes.The Optionee hereby agrees that any
Shares that are transferred to the Optionee (or Beneficiary) pursuant to the exercise of the Option may be subject to the payment of or reduced by any amount or amounts that the Company is required to
withhold under the then applicable provisions of the Internal Revenue Code of 1986, as amended (the "Code"), or its successors, or any other federal, state or local tax withholding requirement (the
"Withholding Amount"). When the Company is required to withhold the Withholding Amount under the applicable provisions of law, the Optionee hereby agrees to satisfy such requirement either by
(a) paying to the Company, in cash or by certified or cashier's check, an amount equal to the Withholding Amount, and/or (b) authorizing the Company to withhold the Withholding Amount
from any cash or other compensation otherwise payable to the Optionee, provided that, to the extent that the Optionee does not remit the entire Withholding Amount by one or a combination of such
methods, the Company may at its election withhold from the Shares otherwise to be delivered to the Optionee that number of Shares having a fair market value, as determined by the Company, equal to the
remaining Withholding Amount.

15.Governing Law.This Agreement shall be governed by,
construed and enforced in accordance with the laws of the State of Delaware.

[Signature page follows]

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This
Agreement is executed and delivered, in duplicate, pursuant to the Plan, the provisions of which are incorporated herein by reference.

|                                       |  |          |  |                     |  | 
|-------------------------------------- |  | -------- |  | ------------------- |  | 
|EMERGENCY MEDICAL SERVICES CORPORATION |  | OPTIONEE |  |                    
|By:                                    |  |          |  |                    
|                                       |  | Name:    |  | (signature)        
|                                       |  | Title:   |  | (print name)       
|                                       |  |          |  |                     |  | 
|                                       |  |          |  | Address:           
|                                       |  |          |  | Facsimile No.       |  | 
|                                       |  |          |  | Social Security No. |  | 

OPTION GRANTED

The
Option granted hereby is as follows:

Name
of Optionee:

Date
of Grant:

Number
of Shares of Class A Stock:

Exercise
Price:

BENEFICIARY DESIGNATION

I HEREBY DESIGNATE THE FOLLOWING PERSON(S) AS MY BENEFICIARY(IES) IN ACCORDANCE WITH SECTION 8 OF THE FOREGOING AGREEMENT:

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(Print
name(s), address(es) and Social Security No.(s)

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(Optionee's
signature)

[Signature page to Nonqualified Stock Option Agreement]

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NONQUALIFIED STOCK OPTION  EXERCISE FORM

EMERGENCY
MEDICAL SERVICES CORPORATION
6200 S. Syracuse Way
Suite 200
Greenwood Village, CO 80111

The
undersigned holder of an Option to purchase  shares of Class A Common Stock granted by
EMERGENCY MEDICAL SERVICES CORPORATION pursuant to a
Nonqualified Stock Option Agreement, dated
, 2007, hereby irrevocably
exercises the right to acquire and subscribe for those securities identified below
issuable on the exercise of all or part of such Option, as applicable, on the terms specified in the said Option Agreement, the Plan and all instruments supplemental thereto:

Number of Shares of Class A
Common Stock to be acquired:Exercise Price per Share:Aggregate Exercise Price payable:


and
hereby tenders a certified check or cash for such aggregate Exercise Price, and directs such securities to be registered in the holder's name and recorded on the stock register of Emergency
Medical Services Corporation as set out below.

The
holder of this Option hereby acknowledges and agrees that: (i) before the securities referred to above will be issued or any payment with respect to this Option will be made, the holder of
this Option must pay, or make arrangements satisfactory to the Company with respect to the payment of, any amount necessary to comply with any U.S. federal, state or local tax withholding requirements
that apply as a result of the exercise hereof (or payment made with respect to this Option).

Dated
this  day of  ,

(Signature of Holder)(Print Full Name)(Address)


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INSTRUCTIONS:

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