Exhibit 4.2 

RESTRICTED STOCK UNIT
AGREEMENT

     AGREEMENT
made this __th day of ____, 2008, between ENTERPRISE FINANCIAL SERVICES CORP, a
Delaware corporation (the "Company"), and __________________________
("Employee").

     1. AWARD.

     (a) UNITS. The Company hereby awards
and issues to Employee _____ restricted stock units (the "Units"). Each Unit
represents the right to receive one share of Restricted Stock under the
Company's 2002 Stock Incentive Plan (as amended from time to time, the "Plan")
subject to the terms of the Plan (including, without limitation, adjustment of
the ratio of converting Units into Restricted Stock provided for in the Plan)
and to the vesting requirements set forth herein.

     (b) ISSUANCE OF UNITS. The Units
shall be evidenced by this Agreement and deemed issued upon acceptance hereof by
Employee.

     (c) PLAN INCORPORATED. The terms and
conditions of the Plan are incorporated herein by reference. Employee
acknowledges receipt of a copy of the Plan (as amended and restated to the date
hereof) and agrees that this award of Units shall be subject to all of the terms
and conditions set forth in the Plan, including future amendments thereto, if
any, provided, however, that no such future amendment shall have an effect upon
the vesting requirements set forth herein or impose additional vesting
requirements or extend restrictions on Restricted Stock beyond the time of
vesting. Capitalized terms not otherwise defined herein shall have the meaning
set forth in the Plan.

     2. VESTING.

     (a) Vesting
of the Units shall be based upon periods of service subsequent to the date of
award and not on other Qualifying Performance Criteria. Units shall vest in
accordance with the following schedule provided that Employee is employed by the
Company on the Vesting Date:


	  				Cumulative 
	  		Percentage
      of 		Vesting
    
	Vesting Date  	     	Units Vesting 	     	Percentage 
	December 15, 20__ - 	 	 20% 	 	  20% 
	December 15, 20__
      - 	 	 20% 		 
      40% 
	December 15, 20__ - 		 20% 		  60% 
	December 15, 20__
      - 		 20% 		 
      80% 
	December 15, 20__ - 		 20% 		100% 




As of each such vesting date, the Units
shall be converted into shares of Restricted Stock under the Plan and the
Company shall issue such shares to Employee by means of book entry and shall,
upon request of the Employee, issue a certificate representing such shares and
Employee shall have all rights of a shareholder of record with respect to such
shares from and after such date. Employee shall have neither the right to vote
nor the right to receive cash dividends or distributions nor any other rights as
a shareholder with respect to the Units prior to the date of vesting.


 

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Exhibit 4.2 

     (b) Vesting
of the Units shall occur upon death, Disability or Retirement (as defined below)
as follows: 

	      	 	      	i.		In the event of the
      death of an Employee while continuing to be employed by the Company, all
      Units not otherwise vested shall become immediately vested and
      exercisable.
		 		ii.	   	In the event of the
      Disability or Retirement of an Employee, all Units shall continue to vest,
      as though Employee had remained employed with the Company following such
      Disability or Retirement, subject to the forfeiture provisions of
      Subparagraph (d) below.
		 
		(c)
      As used herein,
		 
		 		i.		"Retirement" means the
      termination of employment, other than for reasons that constitute
      deliberate gross misconduct, determined in the sole discretion of the
      Committee, after the time that the Employee has attained 60 years of age
      and the sum of his attained age and his continuous full years of full time
      employment service with the Company is 70 (e.g., having attained the age
      of 60 with 10 years of employment with the Company or age 65 with 5 years
      of employment with the Company would qualify the employee for Retirement).
      For these purposes, an employee will be deemed to have a year of full time
      employment service with the Company if the employee would be entitled to
      receive credit for a year of service under a qualified pension plan in
      accordance with Internal Revenue Service Code §1053(b)(2)(c).
		 		ii.		"Disability" shall
      mean qualification for disability benefits under the Social Security
      disability insurance program, or if an employee is determined to be
      permanently disabled by the Committee in its
  discretion.


     (d) Notwithstanding the
provisions of Subparagraph (b) ii. above, the Employee will forfeit all unvested
Units and vesting of Units shall immediately terminate in the event of the
determination of the Committee, made in its sole discretion, that any of the
following has occurred: 

		 		i.		The Employee violates
      any provisions of this Agreement or any other agreement between the
      Company and the Employee;
	      	 	      	ii.		The Employee directly
      or indirectly, owns equity or stock in, manages, operates, is employed by
      or is connected with as an officer, employee, partner, consultant or
      otherwise, or otherwise engages or participates in any entity or business
      engaged in the operation, ownership or management of a bank, trust
      company, wealth management or financial services business within the
      Metropolitan Statistical Areas of St. Louis, Kansas City, Phoenix or any
      other city in which the Company or any of its direct or indirect
      affiliates or subsidiaries has an office at the time of such termination
      (a “Competitive Activity”). Notwithstanding the foregoing, the ownership
      by Employee of less than 1% of any class of the outstanding capital stock
      of any corporation conducting such a competitive business which is
      regularly traded on a national securities exchange or in the
      over-the-counter market shall not be a violation of the foregoing
      covenant.
		 		iii.		The Employee
      utilizes or discloses any confidential or proprietary information
      concerning the Company or any of its customers;
		 		iv.	   	The Employee, directly
      or indirectly, whether alone or in association, or combination with any
      other Person, or as an officer, director, shareholder, member, manager,
      employee, agent, independent contractor, consultant, advisor,
      joint-venturer, partner or otherwise, and whether or not for pecuniary
      benefit (i) solicits, takes away, attempts to take away, diverts, or
      attempt to diverts any customer from the Company or its Affiliates or (ii)
      induces, attempts to induce or aids any person in inducing any customer to
      cease doing business with the Company or any of its Affiliates or in any
      way interfere with the relationship between any customer and the Company
      or its Affiliates.


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Exhibit 4.2 

		 		v.		Employee is employed
      by or acts as a consultant for any person which directly, or through any
      of its Affiliates, solicits, takes away, attempts to take away, diverts,
      or attempts to divert any customer from the Company or any of its
      Affiliates.
	      	 	      	vi.		Employee (i) directly
      or indirectly, entices or induces, or attempts to, entice or induce, or
      directly or indirectly assists any Person in which Employee is an
      investor, consultant or employee to entice or induce, any employee of the
      Company or its Affiliates to leave such employ or (ii) directly or
      indirectly, and shall not be employed or act as a consultant for any
      Person who employs any employee of the Company or its Affiliates in any
      business that engages in any Competitive Activity.
		 		vii.	   	The Employee makes any
      disparaging comments concerning the Company or any of its officers or
      directors, or engages in any other activity or conduct which is
      detrimental to the interests of the Company, as determined by the
      Committee in its sole discretion.



For purposes of this Subparagraph (d)
(including Subparagraphs i through vii) "Company" means the Company and each of
its direct or indirect majority owned subsidiaries and affiliates. 

     3. WITHHOLDING OF TAX. To the extent that
the vesting of Units or receipt of shares of Restricted Stock results in income
to Employee for federal, state or local income tax purposes, Employee shall pay
to the Company, or make arrangements satisfactory to the Committee regarding
payment of, any federal, state or local taxes of any kind required by law to be
withheld with respect to such income. The Company shall, to the extent permitted
by law, have the right to deduct any such taxes from any payment of any kind
otherwise due to the Employee, including the right but not the obligation to
effect such withholding by offset against the shares of Restricted Stock
deliverable in respect of vested Units.

     4. SALE OR TRANSFER OF UNITS OR STOCK.
Employee agrees that the Units may not be sold, transferred or otherwise
disposed of in any manner prior to vesting. Employee also understands that
although the issuance of grants and awards under the Plan has been registered
under the Securities Act of 1933, such registration does not apply to any resale
or transfer by Employee of the shares of stock resulting from vesting of units
under this award and the Plan. Employee also agrees (i) that the certificates
representing the Restricted Stock may bear such legend or legends as the
Committee deems appropriate in order to assure compliance with applicable
securities laws, (ii) that the Company may refuse to register the transfer of
the Restricted Stock on the stock transfer records of the Company if such
proposed transfer would in the opinion of counsel satisfactory to the Company
constitute a violation of any applicable securities law, and (iii) that the
Company may give related instructions to its transfer agent to stop registration
of the transfer of the Restricted Stock.

     5. EMPLOYMENT RELATIONSHIP. For purposes
of this Agreement, including determination of vesting, Employee shall be
considered to be in the employment of the Company as long as Employee remains an
employee of either the Company, any successor corporation (including any parent
entity succeeding to the business of or control of the Company) or subsidiary
corporation (as defined in Section 424 of the Code) of the Company or any
successor corporation. Any question as to whether and when there has been a
termination of such employment, and the cause of such termination, shall be
determined by the Committee, and its determination shall be final and binding on
all persons, including Employee.

     6.
COMMITTEE'S POWERS. No provision contained in this Agreement shall in any way terminate,
modify or alter, or be construed or interpreted as terminating, modifying or
altering any of the powers, rights or authority vested in the Committee pursuant
to the terms of the Plan, including, without limitation, the Committee's rights
to make certain determinations and elections with respect to the Units and
Restricted Shares.

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Exhibit 4.2 

     7. CONFIDENTIALITY; NON SOLICITATION. In
consideration for the grant of Units, Employee agrees as follows:

     (a) For a period of six months
following any termination from the Company, (i) Employee, directly or
indirectly, whether alone or in association, or combination with any other
Person, or as an officer, director, shareholder, member, manager, employee,
agent, independent contractor, consultant, advisor, joint-venturer, partner or
otherwise, and whether or not for pecuniary benefit shall not (A) solicit, take
away, attempt to take away, divert, or attempt to divert any customer from the
Company or its Affiliates or (B) induce, attempt to induce or aid any person in
inducing any customer to cease doing business with the Company or any of its
Affiliates or in any way interfere with the relationship between any customer
and the Company or its Affiliates and (ii) Employee shall not be employed by or
act as a consultant for any person which directly, or through any of its
Affiliates, solicits, takes away, attempts to take away, diverts, or attempts to
divert any customer from the Company or any of its Affiliates.

     (b) For a period of six months
following any termination from the Company, Employee shall not (i) directly or
indirectly, entice or induce, or attempt to, entice or induce, or directly or
indirectly assist any Person in which Employee is an investor, consultant or
employee to entice or induce, any employee of the Company or its Affiliates to
leave such employ or (ii) directly or indirectly, and shall not be employed or
act as a consultant for any Person who employs any employee of the Company or
its Affiliates in any business that engages in any Competitive Activity.


     (c) Employee
shall always refrain from any direct or indirect use or disclosure (whether
intentional, negligent or reckless) of any trade secret or confidential or
proprietary information of the Company to any person or business, without regard
to the nature of Employee’s termination from the Company. 

Employee acknowledges that any violation
of paragraphs (a) through (d) above will cause the Company severe, immediate and
irreparable harm entitling the Company to injunctive relief in addition to any
other remedies that may be available at law or in equity. As used herein, the
term “Company” shall include the Company, its successors, subsidiaries and
affiliates. The provisions of paragraphs (a) through (d) above shall be in
addition to any other noncompetition, nonsolicitation or confidentiality
agreements to which Employee is subject and not supersede or override any such
other agreements. The provisions of paragraphs (a) through (c) above shall
terminate prospectively after any Change of Control as defined in the Plan.


     8. BINDING EFFECT. This Agreement shall
be binding upon and inure to the benefit of the Company, its subsidiaries and
any of their respective successors, and all persons lawfully claiming under
Employee.

     9. GOVERNING LAW. This Agreement shall be
governed by, and construed in accordance with, the laws of the State of
Missouri.

[The remainder of this page is blank.
The next page is the signature page.] 

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Exhibit 4.2 

     IN WITNESS
WHEREOF, the Company has caused this Agreement to be duly executed by an officer
thereunto duly authorized, and Employee has executed this Agreement, all
effective as of the date first above written.


	ENTERPRISE
      FINANCIAL SERVICES CORP 
	 
	 
	By: 
    	 	 
	Name: 	 
	Title: 	 	 
	  
	  
	  
	 
	EMPLOYEE  




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