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                                                                   Exhibit 10.18

                        SEPARATION AND RELEASE AGREEMENT

     THIS SEPARATION AND RELEASE AGREEMENT ("Agreement") is made this 26th day
of August, 2005, effective as of the close of business August 26, 2005
("Effective Date"), by and between Ameritrade Holding Corporation, and its
successors and assigns (collectively, the "Company") and Kurt D. Halvorson,
Executive Vice President and Chief Administrative Officer, his heirs,
representatives, affiliates, successors and assigns (collectively the
"Employee").

                                   WITNESSETH:

     WHEREAS, Employee and the Company are parties to an Employment Agreement
dated September 9, 2002, (the "Employment Agreement") pursuant to which Employee
is employed by the Company; and

     WHEREAS, the Company and Employee agree that the Employee's employment
under the Employment Agreement shall terminate without cause as of close of
business on August 26, 2005, and

     WHEREAS, the Company recognizes Employee's longstanding, unique and
valuable contributions made over his 18 years of loyal service to the Company;
and

     WHEREAS, as a condition precedent to Employee receiving certain of the
severance benefits enumerated in the Employment Agreement, Employee and Company
agreed to execute this Agreement.

     NOW, THEREFORE, in consideration of the covenants undertaken in this
Agreement, including the release contained herein, the parties agree as follows:

     1.   Severance Payments In full and complete satisfaction of Employee's
          claims under the Employment Agreement, including, but not limited to,
          salary, vacation, bonus, stock options, severance, change in control
          payments, incentive pay, sick pay, benefits, holiday, out placement
          services and other compensation of any kind, and as consideration for
          the promises contained in this Agreement, including but not limited to
          the release set forth in paragraph 6 herein, upon the later to occur
          of (a) expiration of the seven (7) day revocation period explained in
          Section 15 below, or (b) the Effective Date ("Expiration Date") and
          subject to Employee's compliance with the terms of this Agreement, the
          Company agrees to provide Employee with the following payments and
          benefits, as reiterated below for convenience:

               a.   The Company shall pay Employee a base salary sum equal
                    to three-hundred-thousand dollars ($300,000) (the "Base
                    Salary") pursuant to Section 6(e)(x) of the Employment
                    Agreement. A portion of the Base Salary in


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                    the amount of
                    one-hundred-forty-nine-thousand-nine-hundred-ninety-nine
                    dollars and eighty-nine cents ($149,999.89) shall be payable
                    in a lump sum approximately six (6) months after Effective
                    Date on March 10, 2006, with the remaining Base Salary paid
                    in equal installments of
                    eleven-thousand-five-hundred-thirty-eight dollars and
                    forty-seven cents ($11,538.47) (any payments shall have all
                    applicable federal, state and local taxes withheld), with
                    such remaining payments to be payable pursuant to Company's
                    regular payroll schedule commencing on March 24, 2006 and
                    ending on September 8, 2006 ;

               b.   The Company shall pay Employee Earned Bonus at Target,
                    pro-rated for the period employed during fiscal year 2005,
                    paid pursuant to the termination provisions of Section 6(b)
                    in the Employment Agreement in the amount of
                    five-hundred-forty-three-thousand-four-hundred-twenty
                    dollars ($543,420), representing 90.57% of $600,000 and
                    payable on September 9, 2005;

               c.   Employee shall receive payment of his accrued but unused
                    paid time off (the "PTO") balance, payable on September 9,
                    2005;

               d.   An annual Bonus at Target in the amount of
                    six-hundred-thousand dollars ($600,000), payable pursuant to
                    Section 6(e)(y) of the Employment Agreement and paid at the
                    same time as other MIP participants receive their MIP
                    bonuses, on or about October 31, 2005;

               e.   A special bonus of one-million-eight-hundred-thousand
                    dollars ($1,800,000) to be paid January 13, 2006;

               f.   If the Employee or any of his dependents are participating
                    in medical and dental coverage under any Company group
                    medical or dental plan, the Company will pay the employer
                    premium costs of the coverage (the "Employer Premium") for
                    twelve (12) months from September 1, 2005 through August 31,
                    2006 (the "Covered Period"). Employee will pay the employee
                    portion of monthly premiums (the "Employee Premium") by
                    remitting a check payable to the Company by the tenth (10th)
                    of each month, commencing in September 2005 in the amount of
                    two-hundred-twenty-nine dollars and ninety cents ($229.90)
                    for medical and thirty-six


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                    dollars and seventy-two cents ($36.72) for dental coverage.
                    Employee Premium may be adjusted as rates change for all
                    employees (the "New Rates") and Company will notify Employee
                    of such rate change. Company will pay to the Employee an
                    amount equal to monthly Employee Premiums, subject to New
                    Rates as applicable and grossed up for taxes at supplemental
                    withholding rates on the first regularly scheduled payroll
                    dates of each month during the Covered Period. To the extent
                    Employee is eligible for medical or dental coverage under
                    another plan (the "Other Coverage"), Employee will
                    immediately notify Company and Company will cease Company
                    medical or dental coverage coincident with the end of the
                    calendar month Employee is eligible for Other Coverage. To
                    the extent that Employee is not eligible for Other Coverage,
                    at the end of the Covered Period, Employee shall be eligible
                    for COBRA continuation coverage (as described in Section
                    4980B of the Internal Revenue Code of 1986, as amended).

               g.   Employee's Company stock options shall be governed by the
                    terms of the respective stock option agreements and the
                    applicable plan document.

          Except as provided herein, Employee will be entitled to no other or
          further compensation, remuneration, payments or benefits of any kind,
          including but not limited to bonuses, paid time off hours, profit
          sharing and/or 401(k) plan Company contributions, insurances and other
          salary continuation benefits. However, nothing in this Agreement is
          intended to divest Employee of any vested rights, if any, in a Profit
          Sharing and/or 401(k) plan.

     2.   Assignment of Claims. In consideration of the payments and benefits to
          Employee in Section 1 herein, and Employee's execution of this
          Agreement, and as an express condition of this Agreement, Employee
          hereby represents and warrants that, up through the date on which this
          Agreement is executed by the parties, he has not assigned or
          transferred, and he will not after such date assign or transfer, (a)
          any claims against the Company, (b) any rights that he may have had to
          assert compulsory or permissive counterclaims against the Company, or
          (c) any rights that he has or may have to aforesaid payments and
          benefits.


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     3.   Return of Property. Employee hereby agrees that, within ten (10)
          calendar days after the Effective Date, he shall turn over to the
          Company all company equipment and property, including but not limited,
          to computers, printers, and related equipment, cell phones, pagers,
          Company Credit cards, and keys, as well as originals and copies of
          notes, correspondence, memoranda, records, documents, computer disks
          and files, and all other information or products, no matter how
          produced or reproduced, pertaining to the business of the Company, its
          subsidiaries, affiliates, officers, and shareholders ("Company
          Materials"), it being hereby acknowledged that all of said items are
          the sole and exclusive property of the Company. Employee's signature
          on this Agreement shall serve as a representation and warranty that
          Employee has not retained any originals or copies of Company
          Materials.

     4.   Non-Compete and Confidentiality. As an inducement for the Company to
          enter into this Agreement and in furtherance of the terms of the
          Employment Agreement, Employee expressly agrees that he provides
          unique and specialized services, skills and expertise to the Company,
          and that the Company hired him because of the unique and specialized
          services, skills and expertise he is able to provide. Employee further
          expressly agrees that he has been given access to Confidential
          Information and trade secrets of the Company and Ameritrade and their
          subsidiaries (collectively "Ameritrade"). Accordingly, Employee
          acknowledges and reaffirms his obligations under the terms of Sections
          4 and 5 of the Employment Agreement through the Effective Date and for
          a 12 month period thereafter ("Restricted Period").

     5.   Remedies for Breach The parties agree that it will be very difficult
          to determine damages caused to the Company should there be a breach by
          Employee of the provisions of this Agreement, including, but not
          limited to, Section 4, and therefore, in addition to any other rights
          or remedies afforded to the Company and not as a penalty, further
          agree that if a breach of any of the provisions of this Agreement or
          the Employment Agreement occurs (Forfeiture Event), Employee will
          immediately forfeit all severance payments and benefits paid or due to
          be paid under Section 1 above ("Forfeited Amount").

          Payment to the Company of any Forfeited Amount will be made by any or
          all of the following methods, at the sole discretion of the CEO of the
          Company to recoup the Forfeited Amount:

               i.   The Company may subtract any Forfeited Amount from any
                    payment payable to the Employee by the Company or any
                    related entity after the Forfeiture Event, and/or


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               ii.  The Employee will pay to the Company any Forfeited Amount
                    which is not repaid to the Company pursuant to paragraph i.
                    above within 30 days of the Forfeiture Event.

     6.   Release. Except for claims based upon a breach of this Agreement, in
          consideration of the promises contained in this Agreement and the
          payments set forth in Section 1 hereof, Employee hereby releases and
          forever discharges the Company, its subsidiaries and affiliates, and
          its officers, directors, shareholders, representatives, agents,
          predecessors, employees, successors and assigns (hereinafter
          collectively and individually the "Company Releasees") from and
          concerning any and all liabilities, rights, claims, demands, debts,
          dues, sums of money, accounts, attorney's fees, complaints, judgments,
          executions, actions and causes of action of any nature whatsoever,
          from the beginning of the world through the Effective Date, whether
          known or unknown, contingent or noncontingent, that Employee may now
          or in the future have against Company Releasees, including but not
          limited to any damages, harms, personal injuries or any rights,
          claims, complaints or actions or causes of action which were or could
          have been asserted by Employee arising out of or related to his work
          for the Company or his separation therefrom, or not being hired by
          Ameritrade, or any other relationship with Company Releasees, or under
          any local, state, or federal human rights, civil rights, labor,
          employment, contract, tort or other laws including, but not limited
          to, those dealing with employment discrimination, including Title VII
          of the Civil Rights Act of 1964, as amended, the Americans with
          Disabilities Act, the Employee Retirement Income Security Act of
          1974, as amended ("ERISA") and the Worker Adjustment and Retraining
          Notification Act of 1988. This release is not intended to waive any
          rights or claims that may arise after the date Employee signs this
          Agreement. Employee agrees to hold Company harmless from any costs or
          expenses, including without limitation, attorney fees, if sued by
          Employee or Employee's assignee, with respect to any of the claims
          released in this section.

     7.   Proceedings. Employee represents that he has not sued or commenced any
          proceeding, and except for claims based upon a breach of this
          Agreement, hereby covenants and agrees not to sue, file any grievances
          or arbitration or commence any other proceeding, administrative or
          judicial, against the Company or the Company Releasees, in any court
          of law or equity, or before any administrative agency, with respect to
          any matter arising from or relating to Employee's employment with the
          Company, his separation thereof, or otherwise.

     8.   Non-Disparagement/Non-Disclosure. Employee shall not disparage or make
          negative, derogatory or defamatory statements about the Company, its
          business activities, or any of its directors, officers, employees,
          affiliates, agents, or representatives, or any of them, to the press,
          any person or


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          business entity. The Company agrees that it shall not disparage or
          make negative, derogatory statements about the Employee. Disparagement
          shall in no event include statements of testimony provided pursuant to
          or in connection with legal regulatory matters. Employee agrees not to
          disclose the contents of this Agreement, unless required by law. This
          restriction will not apply to disclosure by Employee to members of
          immediate family or to legal, tax or financial advisors; provided that
          they are advised of this provision and Employee uses his best efforts
          to protect against any further disclosure by these persons.

     9.   Termination Cause; No Reinstatement or Hire. The Company and the
          Employee acknowledge and agree that Employee's employment with the
          Company will end on August 26th, 2005. Employee agrees that by signing
          this Agreement and accepting the Severance Benefits that he is giving
          up any right that he has, or may have, to reapply for, be reinstated
          to, or to be hired for a position with the Company or any of the
          Company Releasees.

     10.  Transition. The Employee agrees to use reasonable efforts to cooperate
          with the Company, for whatever period of time the Company deems
          reasonably necessary, to ensure a smooth transition of his duties,
          provided that such cooperation does not unduly interfere or conflict
          with his duties as an employee of any entity other than the Company
          and does not require Employee to incur any out of pocket cost or
          expense.

     11.  Adequate Consideration. Employee expressly acknowledges that he has
          received adequate consideration in exchange for the release given in
          this Agreement, and the other obligations contained herein, and
          covenants that he will not in any way seek to challenge this Agreement
          on the grounds of lack of consideration.

     12.  Governing Law. This Agreement shall be construed in accordance with
          the laws of the State of Nebraska, without regard to the conflict of
          law provisions of any state or jurisdiction, to the extent not
          preempted by ERISA.

     13.  Arbitration. ANY CONTROVERSY OR CLAIM ARISING OUT OF OR RELATING TO
          THIS AGREEMENT (OR THE BREACH THEREOF) OR EMPLOYMENT OR CESSATION OF
          EMPLOYMENT BY COMPANY AND NOT OTHERWISE RELEASED, SHALL BE SETTLED BY
          FINAL, BINDING AND NONAPPEALABLE ARBITRATION. EXCEPT AS OTHERWISE
          EXPRESSLY PROVIDED IN THIS PARAGRAPH 13, THE ARBITRATION SHALL BE
          CONDUCTED IN ACCORDANCE WITH THE RULES OF THE AMERICAN ARBITRATION
          ASSOCIATION (THE "ASSOCIATION") THEN IN EFFECT. THE ARBITRATOR CHOSEN
          BY THE PARTIES SHALL BE A FORMER JUDGE. ANY AND ALL PROCEEDINGS,
          HEARINGS, FINDINGS OR ANY OTHER RECORD OF A DISPUTE SO INVOLVED,
          INCLUDING BUT NOT LIMITED TO THE PARTIES TO THIS AGREEMENT AND ANY
          APPOINTED ARBITRATOR SHALL BE CONFIDENTIAL. Nothing in this paragraph
          shall be construed to limit


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          the Company's ability to obtain equitable relief with respect to any
          matter or controversy arising from an alleged actual or threatened
          breach of paragraph 5 of this Agreement without first being required
          to arbitrate such matter or controversy.

     14.  Counterparts. This Agreement may be signed in multiple counterparts,
          each of which shall be deemed to be an original for all purposes.

     15.  Acknowledgement. Employee acknowledges that he has carefully read and
          fully understands the terms and provisions of this Agreement; that he
          is legally competent, and capable of signing this Agreement; that he
          has been cautioned to consult with an attorney prior to signing this
          Agreement; and that sufficient opportunity had been made available to
          him to consult with an attorney to consider the terms of this
          Agreement and that he has availed himself of that right. Employee
          further acknowledges that he has not relied upon any oral
          representation or statement by the Company or its representation or
          statement by the Company or its representatives, which is not set
          forth in this Agreement. Employee shall have the right to revoke this
          Agreement at any time up to seven (7) days following his execution of
          the Agreement. This Agreement shall not be enforceable or effective
          until after the seven-day revocation period has expired.

     16.  Cooperation. Employee agrees to cooperate fully with Company in any
          matters that may have or may result in a proceeding or legal claim
          against the Company, and of which Employee may have knowledge as a
          result of his employment. This requires Employee, without limitation
          to (1) make himself available upon reasonable request to provide
          information and assistance to the Company on such matters without
          additional compensation, except for reimbursement of your
          out-of-pocket costs, and (2) notify the Company promptly or any
          requests to him for information related to any pending or potential
          legal claim or litigation involving the Company, reviewing any such
          request with a designated representative of the Company prior to
          disclosing any such information, and permitting the representative of
          the Company to be present during any communication of such
          information. Notwithstanding anything to the contrary, the Company's
          obligation to reimburse Employee for costs will not apply to any
          proceeding in which Employee or his interests are, in whole or in
          part, as determined by the Company, adverse to those of the Company,
          or if such proceeding involves, in whole or in part, Employee's breach
          or alleged breach of his obligations under this Agreement or the
          violation of any obligation which Employee owed to the Company during
          the course of or in connection with employment by the Company.

     17.  Entire Agreement. This Agreement, the Employment Agreement through the
          Effective Date and the surviving provisions of the Employment
          Agreement after the Effective Date constitute the entire understanding
          of


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          the parties, supersedes all prior oral or written agreements, and
          cannot be modified in nor any of its conditions waived, except by a
          writing signed by both parties. No agreements or representations, oral
          or otherwise, expressed or implied, with respect to the subject matter
          hereof have been made by any party, which are not set forth expressly
          in this Agreement. To the extent of any inconsistency between the
          terms of this Agreement and the terms of the Employment Agreement, the
          terms of this Agreement will control.

     18.  Section 409A of the Code. The Company and the Employee agree to work
          together in good faith to consider, as applicable, (i) any amendment
          to this Agreement or (ii) any revisions to the manner of any payment
          of benefits under this Agreement, which may be necessary or
          appropriate to avoid imposition of any additional tax or income
          recognition prior to the actual payment to Employee under Section 409A
          of the Code and any temporary or final Treasury Regulations and
          Internal Revenue Service guidance thereunder.

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
set forth below.

                                        AMERITRADE HOLDING CORPORATION


Date: 8/26/05                           By: /S/ JOSEPH H. MOGLIA
                                            ------------------------------------
                                        Name: Joseph H. Moglia
                                        Title: CEO


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                    ACKNOWLEDGMENTS AND CERTIFICATIONS:

YOU ACKNOWLEDGE AND CERTIFY THAT YOU:

     (A)  HAVE READ AND UNDERSTAND ALL OF THE TERMS OF THIS AGREEMENT AND DO NOT
          RELY ON ANY REPRESENTATION OR STATEMENT, WRITTEN OR ORAL, NOT SET
          FORTH IN THIS AGREEMENT;

     (B)  UNDERSTAND THAT THIS AGREEMENT SPECIFICALLY APPLIES TO ANY RIGHTS OR
          CLAIMS YOU MAY HAVE AGAINST AMERITRADE OR ANY RELEASED PARTY UNDER THE
          FEDERAL AGE DISCRIMINATION IN EMPLOYMENT ACT OF 1967, AS AMENDED;

     (C)  UNDERSTAND THAT THIS AGREEMENT DOES NOT PURPORT TO WAIVE RIGHTS OR
          CLAIMS THAT MAY ARISE FROM ACTS OR EVENTS OCCURRING AFTER THE DATE
          THAT THIS AGREEMENT IS EXECUTED BY YOU;

     (D)  HAVE HAD A REASONABLE PERIOD OF TIME TO CONSIDER THIS AGREEMENT;

     (E)  ARE SIGNING THIS AGREEMENT KNOWINGLY AND VOLUNTARILY;

     (F)  HAVE BEEN ADVISED TO CONSULT WITH AN ATTORNEY BEFORE SIGNING THIS
          AGREEMENT;

     (G)  HAVE THE RIGHT TO CONSIDER THE TERMS OF THIS AGREEMENT FOR 45 DAYS AND
          IF YOU TAKE FEWER THAN 45 DAYS TO REVIEW THIS AGREEMENT, YOU HEREBY
          WAIVE ANY AND ALL RIGHTS TO THE BALANCE OF THE 45 DAY REVIEW PERIOD;
          AND

     (H)  HAVE THE RIGHT TO REVOKE THIS AGREEMENT WITHIN SEVEN DAYS AFTER
          SIGNING IT (THE "REVOCATION PERIOD") AND THEREFORE THIS AGREEMENT
          SHALL NOT BECOME EFFECTIVE OR ENFORCEABLE UNTIL THE EXPIRATION OF THE
          REVOCATION PERIOD. IF YOU CHOOSE TO REVOKE THIS AGREEMENT, YOU MUST DO
          SO BY NOTIFYING AMERITRADE IN WRITING DELIVERED TO

               AMERITRADE
               ATTN: KELLI EICKHOFF
               4211 S. 102ND STREET
               OMAHA, NE 68127

               IF YOU REVOKE THIS AGREEMENT DURING THIS SEVEN-DAY PERIOD, IT AT
               ONCE BECOMES NULL AND VOID IN ITS ENTIRETY.

THIS IS A LEGALLY ENFORCEABLE DOCUMENT.


Date: 8/26/05                           /S/ KURT D. HALVORSON
                                        ----------------------------------------
                                        KURT D. HALVORSON


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