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Exhibit 10.20
                        EXECUTIVE EMPLOYMENT AGREEMENT

  THIS AGREEMENT (the "Agreement") is made effective as of the 21st day of
October, 1999, between FIRST PROFESSIONAL BANK, N.A. ("Employer") and GENE
GAINES ("Executive").

                                   RECITALS
                                   --------

  WHEREAS, Employer desires to employ Executive as its Chief Executive Officer,
and Executive desires to be employed by Employer, on the terms and subject to
the conditions set forth in this Agreement;

  NOW, THEREFORE, in consideration of the foregoing promises and the terms,
covenants and conditions set forth herein, the parties hereto agree as follows:

  1.  Definitions.  For purposes of this Agreement, the definitions set forth on
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Exhibit B hereto shall apply unless the context clearly indicates otherwise.

  2.  Employment and Term.  Employer hereby employs Executive and Executive
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hereby accepts employment, upon the terms and conditions set forth herein.  The
term of this Agreement (the "Term") shall be for a period of one year,
commencing October 20, 1999 and ending on October 19, 2000, unless earlier
terminated in accordance with the provisions hereof.  This Agreement shall
automatically renew for successive one-year periods thereafter, unless
terminated by either party giving written notice of termination to the other
party at least ninety (90) days prior to the expiration of the then-current one-
year term.

  3.  Duties.  Executive shall serve as the Chief Executive Officer of Employer
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and shall perform the duties and have the responsibilities set forth on Exhibit
A attached hereto and incorporated herein by reference, and shall have the
authority and perform such other duties, services and responsibilities incident
to such position as are customary of the Chief Executive Officer of a bank, and
such other reasonable duties and responsibilities as are determined from time to
time by the Board.  Executive shall report to the Board.  Executive shall devote
one hundred percent (100%) of his business time, attention and skill to the
performance of his duties hereunder, except that Executive is permitted to spend
a reasonable amount of business time to complete his obligations under his
Consulting Agreement with Shapiro Consulting Group, and shall perform his duties
to the best of his ability and subject to the policies and instructions of the
Board.  Executive will not, without the prior written approval of Employer,
engage in any other business activity which would interfere with the performance
of his duties, services and responsibilities hereunder or which is in violation
of policies established from time to time by the Board.

  4.  Compensation.
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      (a)  Salary.  Executive will receive an annual base salary of One Hundred
Fifty Thousand Dollars ($150,000) during the Term (the "Annual Base Salary"),
payable in equal bi-weekly installments. Salary payments shall be subject to
withholding and all other applicable taxes. Executive's Annual Base Salary shall
be reviewed at least annually by the Compensation Committee of the Board and may
be increased in the discretion of the Board based upon Executive's performance,
Employer's performance and profitability and other factors generally used by
Employer and in the industry in adjusting salaries of executive employees.

      (b)  Annual Bonus.  Executive may be eligible to receive an annual bonus
in an amount of up to 50% of his Annual Base Salary, based upon the attainment
of either (i) specific corporate budgetary and strategic objectives or (ii)
specific individual performance objectives, any of which shall be set by the
Board. Bonuses, if any, may be payable in a combination of a lump sum cash
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payment and the issuance of options to purchase shares of common stock of
Employer's parent company, Professional Bancorp, Inc. ("PBI"), to be allocated
as mutually agreed upon by the parties.

      (c)  Stock Options.  In consideration of Executive agreeing to enter into
this Agreement, on November 1, 1999, Employer caused PBI to grant to Executive
fully vested stock options to purchase 30,000 shares of PBI's common stock at an
exercise price of $11.16 per share. These 30,000 options shall be exercisable on
the earlier of: (i) the closing of the sale of all or substantially all of the
assets of Employer or PBI to, or the merger of Employer or PBI with, a third
party, (ii) on the fifteen month anniversary date of the effective date of this
Agreement if Employer or PBI has not entered into a Definitive Agreement to sell
all or substantially all of its assets to or to merge with a third party, or
(ii) the date Employer terminates this Agreement at will pursuant to Section
8(e) hereof or Employee terminates this Agreement for Good Cause pursuant to
Section 8(c) hereof. On the nine month anniversary date of the effective date of
this Agreement, if by such date PBI or Employer has not entered into a
Definitive Agreement to sell all or substantially all of its assets to or to
merge with a third party, Employer shall cause PBI to grant to Executive fully
vested and immediately exercisable options to purchase 20,000 shares of PBI's
common stock at an exercise price determined pursuant to the applicable stock
option plan. Executive shall be eligible to receive additional performance-based
options, consistent with PBI's applicable stock option plans, as determined by
the Compensation Committee of the Board. All options are subject to the terms of
the applicable stock option plan(s).

      (d)  Severance.  If Employer terminates this Agreement at will pursuant to
Section 8(e) hereof or if Employee terminates this Agreement for Good Reason
pursuant to Section 8(c) hereof, Employer will continue to pay Executive the
monthly base salary that he is earning at the time of the Notice of Termination
for twelve months following the date of the Notice of Termination.

  5.  Fringe Benefits.
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      (a)  Incentive Plans/Benefits.  Subject to the eligibility requirements of
each plan, Executive shall be entitled to participate in all medical or health
plans, dental and vision plans, life insurance plans, disability plans,
401(K)/savings and retirement plans, welfare plans, incentive plans, equity-
based plans and all other benefits generally available to full-time officers or
senior management employees of Employer in effect from time to time. All
insurance is subject to the terms of the policies in effect and to Executive's
insurability under such policies.

      (b)  Auto Allowance.  Executive shall be entitled to an auto allowance of
Five Hundred Dollars ($500) per month.

      (c)  Vacation.  Executive shall receive twenty (20) paid vacation days per
year.

      (d)  Business Expenses.  In accordance with the policies relating to
Employer's senior executive employees, Employer will reimburse Executive for
reasonable out-of-pocket expenses incurred by Executive in the performance of
his duties hereunder. All such reimbursements will be made upon submission to
Employer of written expense reports or other documentation which describe and
substantiate such business expenses and which are in such form as Employer may
from time to time prescribe for its executive employees.

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  6.  Confidential Information.  Executive acknowledges that in his positions
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with Employer, he will be exposed to and receive information relating to the
confidential affairs of Employer, Employer's subsidiaries and PBI, including but
not limited to, Employer's, Employer's subsidiaries' and PBI's customer lists,
financial information, strategic plans, business and marketing plans and
strategies, information concerning Employer's, Employer's subsidiaries' and
PBI's products, promotions, customers, development, financing, expansion plans,
business policies and practices, and other information considered by Employer,
Employer's subsidiaries and PBI to be confidential, proprietary and in the
nature of trade secrets (the "Confidential Information").  Executive
acknowledges that the Confidential Information is a valuable, special and unique
asset of Employer's, Employer's subsidiaries' and PBI's businesses.  Executive
agrees to keep all Confidential Information confidential and shall not, during
the Term or thereafter, directly or indirectly disclose all or any part of the
Confidential Information in any manner whatsoever to any person, firm,
corporation, association or other entity other than outside professionals
employed by Employer or use such Confidential Information for his own personal
benefit, without the prior written consent of Employer, unless such disclosure
is made in the ordinary course of Employer's business and is necessary and
advances the best interests of Employer.

  7.  Employer Documents.  Executive expressly agrees that all plans, customer
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lists, reports, manuals, documents, files, studies, instruments and other
materials used and/or developed by Executive relating to Employer, Employer's
subsidiaries and PBI and their respective customers are solely the property of
Employer, Employer's respective subsidiary or PBI and that Executive has no
right, title or interest therein.  During Executive's employment with Employer
and after termination thereof, regardless of the reason therefor, Executive
shall hold in a fiduciary capacity for the benefit of Employer, all such plans,
lists, disks, documentation, programs, reports, memoranda, diaries, notes,
records, letters, manuals and all other documents and information of Employer.
Upon termination of Executive's employment for any reason, Executive shall
immediately deliver all such documents, without retaining any copies thereof, to
Employer.

  8.  Termination of Employment.
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      (a)  Death or Incapacity.  This Agreement shall terminate automatically
upon Executive's death during the Term. This Agreement shall also terminate on
the date of the determination by the Board that the Incapacity of Executive has
occurred during the Term ("Incapacity Effective Date").

      (b)  Cause.  Employer may terminate Executive's employment for Cause, as
defined herein.

      (c)  Good Reason.  Executive may terminate his employment for Good Reason,
as defined herein.

      (d)  Written Notice.  Executive may terminate this Agreement at any time
upon ninety (90) days' prior written notice to Employer.

      (e)  At Will.  Employer may terminate this Agreement by written notice to
Executive at any time for any reason.

      (f)  Notice of Termination.  Any termination (except by death) shall be
communicated by a Notice of Termination to the other party hereto given in
accordance with Section 14 of this Agreement. For purposes of this Agreement, a
"Notice of Termination" means a written notice which (i) indicates the

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specific termination provision in this Agreement relied upon, (ii) to the extent
applicable, sets forth in reasonable detail the facts and circumstances claimed
to provide a basis for termination under the provision so indicated, (iii) in
the case of termination by Employer for Cause or for Incapacity, confirms that
such termination is pursuant to a resolution of the Board (which, in the case of
Cause, is pursuant to Section 8(b) hereof), and (iv) if the Date of Termination
(as defined below) is other than the date of such notice, specifies the
termination date. The failure by Executive or Employer to set forth in the
Notice of Termination any fact or circumstance which contributes to a showing of
Good Reason, Incapacity or Cause shall not serve to waive any right of Executive
or Employer, respectively, hereunder or preclude Executive or Employer,
respectively, from asserting such fact or circumstance in enforcing Executive's
or Employer's rights hereunder.

      (g)  Date of Termination.  "Date of Termination" means (i) if Executive's
employment is terminated by Employer for Cause, or by Employer other than for
Cause, death or Incapacity, the date of the Notice of Termination or any later
date specified therein, as the case may be, (ii) if Executive's employment is
terminated by Executive for Good Reason, the Date of Termination shall be thirty
(30) days after the date of the Notice of Termination, however Employer may
specify an earlier date in its discretion after its receipt of the notice from
Executive, (iii) if Executive's employment is terminated by reason of death or
Incapacity, the Date of Termination shall be the date of death of Executive or
the Incapacity Effective Date, as the case may be, and (iv) if Executive's
employment is terminated by Written Notice by Executive, the Date of Termination
shall be ninety (90) days after the date of the Notice of Termination.

  9.  Obligations of Employer Upon Termination.
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      (a)  Obligations Upon Termination.  Upon termination of this Agreement for
any reason, Employer's sole obligation to Executive (except as otherwise
expressly set forth herein) shall be to pay any accrued but unpaid salary or
bonus up to the Date of Termination, less withholding and other taxes as
required by law, and provide to Executive any other accrued amounts or benefits
required to be paid or provided or which Executive is eligible to receive under
any Employer plan in which Executive participated (such other amounts and
benefits shall be hereinafter referred to as the "Accrued Benefits"). Any salary
or bonus shall be paid to Executive within thirty (30) days after the Date of
Termination; and any benefits shall be paid pursuant to the applicable Employer
plan.

      (b)  Excise Tax Limitation.  To the extent that the payments and benefits
provided under this Agreement and payments or benefits provided to, or for the
benefit of, Executive under any other Employer plan or agreement (such payments
or benefits are collectively referred to as the "Payments") would be subject to
the excise tax (the "Excise Tax") imposed under Section 4999 of the Internal
Revenue Code of 1986, as amended, the Payments shall be reduced (but not below
zero) if and to the extent necessary so that no Payment to be made or benefit to
be provided to Executive shall be subject to the Excise Tax.

  10. Non-Exclusivity of Rights.  Nothing in this Agreement shall prevent or
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limit Executive's continuing or future participation in any Employer plan for
which Executive may qualify, nor shall anything herein limit or otherwise affect
such rights as Executive may have under any contract or agreement with Employer
or any of Employer's subsidiaries.  Amounts which are vested benefits or which
Executive is otherwise entitled to receive under any Employer plan at or
subsequent to the Date of Termination shall be payable in accordance with such
plan, policy, practice, program, contract or agreement except as explicitly
modified by this Agreement.

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  11.  Non-Solicitation and Non-Competition.  During the Term hereof, Executive
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agrees that he shall not, directly or indirectly, either individually or as an
owner, partner, director, agent, employee, consultant or otherwise, solicit,
endeavor to entice away from Employer or any of Employer's subsidiaries or
otherwise engage in any activity intended to disrupt or terminate the
relationship of Employer or any of Employer's subsidiaries with any of their
clients, customers, employees or agents.  During the Term hereof, Executive
agrees that he shall not, directly or indirectly, either individually or as an
owner, partner, director, agent, employee, consultant or otherwise, compete with
Employer or any of Employer's subsidiaries or PBI.

  12.  Remedies.  Executive agrees that any breach by Executive of the terms of
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Section 6, 7 or 11 hereof would result in irreparable injury and damage to
Employer and Employer's parents and/or subsidiaries for which Employer and
Employer's parents and subsidiaries would have no adequate remedy at law.
Therefore, in the event of Executive's breach or threatened breach of Sections
6, 7, or 11 hereof, Executive agrees that Employer and Employer's parents and
subsidiaries shall be entitled to an immediate preliminary restraining order and
an injunction restraining and enjoining Executive to prevent such breach or
threatened breach or continued breach by Executive and any and all persons or
entities acting for and/or with Executive, without having to prove damages, and
to all costs and expenses, including reasonable attorneys' fees and costs, in
addition to any other remedies to which Employer or Employer's subsidiaries may
be entitled at law or in equity.  In addition to or in lieu of the above,
Employer or Employer's subsidiaries may pursue all other remedies available to
Employer and Employer's subsidiaries for such breach or threatened breach,
including the recovery of damages and reasonable attorneys' fees, from
Executive.

  13.  Successors; Binding Agreement.  This Agreement shall be binding upon the
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respective successors, assigns, heirs, and representatives of the parties.

  14.  Notices.  Any notice, request or other information to be given or served
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hereunder by any party to another shall be deemed given or served hereunder by
any party to another if in writing and delivered personally or sent by prepaid
registered or certified mail, return receipt requested, to:

       If to Employer:      First Professional Bank, N.A.
                            606 Broadway
                            Santa Monica, California  90401
                            ATTN:  Ms. Julie P. Thompson, Chairman of the Board

       If to Executive:     Mr. Gene Gaines
                            1018 Second Street, Unit 1
                            Santa Monica, California  90403

or to such other address as any party may designate for itself by notice to the
other party given in accordance with the provisions hereof.

  15.  Entire Agreement.  This Agreement contains the entire agreement of the
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parties with respect to the subject matter hereof and supersedes any and all
other agreements or understandings, written or oral, relating to such subject
matter.  Each party to this Agreement acknowledges that no representations,
inducements, promises or agreements, oral or otherwise, have been made by any
party, or anyone acting on behalf of any party, which are not embodied herein,
and that no other agreement, statement or promise not contained in this
Agreement concerning its subject matter shall be valid or binding.

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  16.  Modification; Waiver.  No provision of this Agreement may be modified,
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waived or discharged unless such modification, waiver or discharge is agreed to
in writing and signed by each party hereto.  No waiver by either party hereto at
any time of any breach by the other party hereto of, or compliance with, any
condition or provision of this Agreement to be performed by such other party
shall be deemed a waiver of similar or dissimilar provisions or conditions at
the same or at any prior or subsequent time.

  17.  Non-Assignability.  Executive acknowledges that his services are unique
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and personal.  Accordingly, Executive may not assign any of his rights or
delegate his duties or obligations under this Agreement.

  18.  Governing Law.  This Agreement shall be governed and construed and the
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legal relationship and obligations of the parties determined in accordance with
the laws of the State of California.

  19.  Severability.  Should any provision of this Agreement for any reason be
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declared invalid, void or unenforceable by a court of competent jurisdiction,
the validity and binding effect of any remaining portion shall not be affected,
and the remaining portions of this Agreement shall remain in full force and
effect as if this Agreement had been executed with said provision eliminated.

  20.  Survival.  The provisions of Sections 6, 7, and 11 shall survive the
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termination or expiration of this Agreement.

  21.  Arbitration.  In the event that any dispute shall arise between the
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parties concerning the provisions of this Agreement or the performance of any
part of their obligations hereunder, or in the event of an alleged breach of
this Agreement by either of the parties hereto, and the parties are unable to
mutually adjust and settle same, such dispute or disputes (other than dispute(s)
concerning an alleged or threatened breach by Executive of Sections 6, 7, or 11
hereof) shall be submitted to binding arbitration in Santa Monica or Los
Angeles, California pursuant to the applicable commercial rules of the American
Arbitration Association, and the decision and determination of the arbitrators
shall be final and binding upon the parties.

  22.  Key Person Insurance.  Executive agrees to make all reasonable efforts to
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obtain any key person insurance requested by Employer.

  IN WITNESS WHEREOF, the Bank has caused this Agreement to be executed in its
corporate name by an officer duly authorized to enter into and execute this
Agreement, and Executive has affixed his signature hereto, as of the date and
year first above written.

                               FIRST PROFESSIONAL BANK, N.A.

                               By:
                                  ----------------------------------------
                                  Julie P. Thompson, Chairman of the Board


                               -------------------------------------------
                               GENE GAINES

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                                   EXHIBIT A
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                             POSITION DESCRIPTION
           CHIEF EXECUTIVE OFFICER OF FIRST PROFESSIONAL BANK, N.A.


 .    Fosters a corporate culture that promotes ethical practices, encourages
     individual integrity, and fulfills social responsibility.

 .    Maintains a positive and ethical work climate that is conducive to
     attracting, retaining, and motivating a diverse group of top-quality
     employees at all levels.

 .    Develops and recommends to the Board long-term strategies and visions for
     the Bank that leads to creation of shareholder value.

 .    Develops and recommends to the Board annual business plans and budgets
     and capital plans that support the Bank's long-term strategy.

 .    Ensures that the day-to-day business affairs of the Bank are
     appropriately managed and Bank employees are appropriately supervised.

 .    Consistently strives to achieve the Bank's financial and operating goals
     and objectives.

 .    Ensures continuous improvement in the quality and value of the products
     and services provided by the Bank.

 .    Strives to ensure that the Bank achieves and maintains a satisfactory
     competitive position within its industry.

 .    Ensures that the Bank has en effective management team below the level of
     the Chief Executive Officer, and has an active plan for their development
     and succession.

 .    Ensures, in cooperation with the Board, that there is an effective
     succession plan in place for the Chief Executive Officer position.

 .    Formulates and oversees the implementation of Bank corporate policies.
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                                   EXHIBIT B
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                                  DEFINITIONS

As used in this Agreement:

  (a) "Board" means the Board of Directors of the Employer.

  (b)  "Cause" means (i) willful malfeasance or willful or reckless misconduct
by Executive in connection with his employment duties hereunder, (ii) continuing
refusal by Executive to perform his duties under this Agreement after notice of
such refusal to perform such duties was given to Executive by Employer, (iii)
failure of Executive to cure a material breach by Executive of the provisions of
this Agreement within fifteen (15) days after written notification by Employer
to Executive specifying the breach, (iv) the determination by a state or federal
banking agency or governmental authority having jurisdiction over Employer or
Employer's subsidiaries that Executive is not suitable to act in the capacity
for which he is employed by Employer, (v) Executive's willful and intentional
violation of any federal banking laws, or of the Bylaws, rules, policies or
resolutions of Employer, or of the rules or regulations of the Federal Deposit
Insurance Corporation, OCC or other regulatory agency or governmental authority
having jurisdiction over Employer or Employer's subsidiaries, or (vi) the
commission by Executive of any felony or a misdemeanor involving moral
turpitude. Termination for Cause shall only be made by a resolution adopted in
good faith by a majority of the Board at a meeting of the Board called and held
for that purpose (after ten (10) days prior written notice of the meeting to
Executive and reasonable opportunity for Executive to be heard by the Board at
the meeting prior to such vote.)

  (c)  "Good Reason" shall mean the failure of the Employer to cure any material
breach by Employer of any provision of this Agreement within fifteen (15) days
after written notification by Executive to Employer specifying the breach.

  (d)  "Incapacity" means any permanent physical or mental illness or disability
of Executive which continues for a period of three consecutive months or more
and which at any time after such three-month period the Board shall reasonably
determine renders Executive incapable of substantially performing his duties
during the remainder of the Term.