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                                                                   EXHIBIT 10.15

                      SENIOR EXECUTIVE EMPLOYMENT AGREEMENT

            This Senior Executive Employment Agreement (the "Agreement") is
entered into as of this 26th day of May, 2005 (the "Effective Date") by and
between Mark F. O'Neil ("Executive") and DealerTrack Holdings, Inc., a Delaware
corporation ("Employer") with principal offices at 1111 Marcus Avenue, Suite
M04, Lake Success, NY 11042.

            Section 1. Term

            Employer shall continue to employ Executive and Executive agrees to
continue such employment, upon the terms and conditions hereinafter set forth,
from the Effective Date through and including June 30, 2007 (the "Initial
Term"). This Agreement shall renew automatically for successive one year periods
(each, a "Renewal Term") unless one party gives notice to the other party, in
writing, at least sixty (60) days prior to the expiration of this Agreement (or
any renewal) of its desire to terminate the Agreement. The term of this
Agreement, including the Initial Term and any Renewal Term, shall be referred to
herein as the "Term".

            Section 2. Executive's Duties

            (a) Executive shall be Chairman and Chief Executive Officer and
shall report directly to the Board of Directors of Employer (the "Board").
Executive shall faithfully and diligently perform his duties at the direction of
the Board, or a committee of the Board, to the best of Executive's ability.
Executive shall (i) devote his best efforts, skill, and ability and full
business time and attention to the performance of the services customarily
incident to such office, subject to vacations and sick leave as provided herein
and in accordance with Employer policy, (ii) carry out his duties in a competent
and professional manner; and (iii) generally promote the interests of Employer.
Subject to applicable law, Executive shall not knowingly participate in any
activity that is detrimental to the interests of Employer or any of its
affiliates, including, without limitation, any public criticism or disparagement
of any type by Executive, through the media or otherwise, of Employer or any of
its affiliates or employees, except in connection with the exercise of
Executive's rights against Employer or any of its affiliates.

            (b) Executive agrees to abide by all policies applicable to senior
executive officers of Employer promulgated from time to time by Employer, which
policies are enforced uniformly and applicable to all similar executives of
Employer.

            (c) Except for such business travel as may be incident to his duties
hereunder, Executive shall perform his duties at Employer's offices at the
address set forth in the preamble to this Agreement or at such other location as
may be approved by Employer.

            Section 3. Compensation for Executive's Services

            In consideration of the duties and services to be performed by
Executive pursuant to Sections 1 and 2 hereof, Executive shall receive:

            (a) Salary. Executive shall earn salary (the "Salary") at the annual
rate of Four Hundred Seventy-Six Thousand Dollars ($476,000.00) (the "Minimum
Salary"), less all

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applicable federal, state, and local tax withholdings. Such Salary shall be
earned and shall be payable in periodic installments in accordance with
Employer's payroll practices. During the Term, the Board or the Compensation
Committee of the Board (the "Compensation Committee") will review the Salary
annually and may in its discretion increase the Salary, but may not reduce it
during the Term unless Employer institutes salary reductions across the board;
provided, however, that in no event shall the Salary be reduced below the
Minimum Salary without Executive's written consent.

            (b) Bonus. For each fiscal year of Employer (each, a "Fiscal Year"),
Executive shall be entitled to receive a cash performance bonus (a "Bonus")
which shall be based on the achievement of certain performance benchmarks by
Employer during such Fiscal Year which shall be determined by the Board. The
Board shall review the target Bonus on an annual basis and, in its sole
discretion, may increase such target Bonus for any Fiscal Year. The target Bonus
shall not be decreased except in connection with company-wide bonus reductions.
The target Bonus for any Fiscal Year shall be at least Seventy percent (70%)
percent of the Salary for such Fiscal Year. The Bonus for each Fiscal Year shall
be paid, if at all, to Executive on a schedule consistent with Employer's bonus
payments to its other similarly situated senior executive officers by no later
than two and one half (2-1/2) months following the end of such Fiscal Year.
Executive understands and agrees that the Bonus is established in part as an
inducement for Executive to remain employed by Employer and except as provided
in Section 5(c) of this Agreement, or in the Employer's sole discretion, in the
event that Executive's employment is terminated prior to the end of any Fiscal
Year during the Term, then Executive shall not receive payment of any Bonus for
such year.

            (c) Equity. In connection with Executive's employment, Executive has
been and may continue to be granted stock options ("Stock Options") to purchase
equity securities of Employer pursuant to the terms of DealerTrack Holdings,
Inc. 2001 Stock Option Plan, effective as of August 10, 2001, as amended ("Stock
Option Plan") or may be granted Stock Options or other equity based awards
pursuant to the terms of the DealerTrack Holdings, Inc. 2005 Incentive Award
Plan, effective as of May 26, 2005, as amended (the "2005 Incentive Award
Plan"), or any other successor equity incentive plans (collectively, the "Stock
Incentive Plans"). Except as otherwise provided herein, the terms of the Stock
Options shall be governed by the Stock Incentive Plans. Executive shall be
credited with twenty-four (24) months accelerated vesting of his Stock Options
upon termination of Executive's employment by: (1) Employer without Cause (as
defined below); or (2) Executive for Good Reason (as defined below). Executive
shall be credited with thirty-six (36) months accelerated vesting of his Stock
Options upon a Change of Control (defined below). Executive shall be credited
with full acceleration and vesting of his Stock Options upon the earlier of: (1)
the elimination of Executive's position or a termination of Executive's
employment, in either event, within twelve (12) months after a Change of
Control; (2) a material negative change in Executive's compensation or
responsibilities within twelve (12) months after a Change of Control; or (3) the
requirement that Executive be based at a location which is more than fifty (50)
miles from Employer's offices at the address set forth in the preamble to this
Agreement within twelve (12) months after a Change of Control. Anything in the
Stock Incentive Plans to the contrary notwithstanding, if Executive's employment
is terminated by Executive with Good Reason or by Employer without Cause, or
under circumstances described above which would result in certain accelerated
vesting of any unvested Stock Options held by Executive, the unexercised portion
of any Stock Options held by

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Executive will not terminate until the twelve (12) month anniversary of the date
of termination of Executive's employment. In the event Employer elects to grant
equity based awards other than Options, such grants shall, where appropriate, be
subject to equivalent acceleration provisions as set forth in this Section 3(c).
For purposes hereof, a "Change of Control" shall mean and includes each of the
following:

            (i) A transaction or series of transactions (other than an offering
      of shares of Employer to the general public through a registration
      statement filed with the Securities and Exchange Commission) whereby any
      "person" or related "group" of "persons" (as such terms are used in
      Sections 13(d) and 14(d)(2) of the Securities Exchange Act of 1934, as
      amended) (other than the Employer, any of its subsidiaries, an employee
      benefit plan maintained by the Employer or any of its subsidiaries or a
      "person" that, prior to such transaction, directly or indirectly controls,
      is controlled by, or is under common control with, the Employer) directly
      or indirectly acquires beneficial ownership (within the meaning of Rule
      13d-3 under the Securities Exchange Act of 1934, as amended) of securities
      of the Employer possessing more than 50% of the total combined voting
      power of the Employer's securities outstanding immediately after such
      acquisition; or

            (ii) During any period of two consecutive years, individuals who, at
      the beginning of such period, constitute the Board together with any new
      director(s) (other than a director designated by a person who shall have
      entered into an agreement with the Company to effect a transaction
      described in Section 3(c)(i) or Section 3(c)(iii)) whose election by the
      Board or nomination for election by the Employer's stockholders was
      approved by a vote of at least two-thirds of the directors then still in
      office who either were directors at the beginning of the two-year period
      or whose election or nomination for election was previously so approved,
      cease for any reason to constitute a majority thereof; or

            (iii) The consummation by the Employer (whether directly involving
      the Employer or indirectly involving the Employer through one or more
      intermediaries) of (x) a merger, consolidation, reorganization, or
      business combination or (y) a sale or other disposition of all or
      substantially all of the Employer's assets in any single transaction or
      series of related transactions or (z) the acquisition of assets or stock
      of another entity, in each case other than a transaction:

                  (A) Which results in the Employer's voting securities
            outstanding immediately before the transaction continuing to
            represent (either by remaining outstanding or by being converted
            into voting securities of the Employer or the person that, as a
            result of the transaction, controls, directly or indirectly, the
            Employer or owns, directly or indirectly, all or substantially all
            of the Employer's assets or otherwise succeeds to the business of
            the Employer (the Employer or such person, the "Successor Entity"))
            directly or indirectly, at least a majority of the combined voting
            power of the Successor Entity's outstanding voting securities
            immediately after the transaction, and

                  (B) After which no person or group beneficially owns voting
            securities representing 50% or more of the combined voting power of
            the Successor Entity;

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            provided, however, that no person or group shall be treated for
            purposes of this Section 3(c)(iii) as beneficially owning 50% or
            more of combined voting power of the Successor Entity solely as a
            result of the voting power held in the Employer prior to the
            consummation of the transaction; or

            (iv) The Employer's stockholders approve a liquidation or
      dissolution of the Employer.

The Board or its designee shall have full and final authority, which shall be
exercised in its discretion, to determine conclusively whether a Change of
Control of the Employer has occurred, and the date of the occurrence of such
Change of Control and any incidental matters relating thereto.

            (d) Benefits. Employer shall provide Executive with the right to
participate in and receive benefits from all life, accident, disability, medical
and pension plans, and all similar benefits as are from time to time in effect
and are generally made available to similar situated senior executive officers
of Employer. The amount and extent of benefits to which Executive is entitled
shall be governed by the specific benefit plan, as it may be amended from time
to time.

            (e) Expenses. Employer shall promptly reimburse Executive for
reasonable expenses for cellular telephone usage, entertainment, travel, meals,
lodging and similar items incurred in the conduct of Employer's business. Such
expenses shall be reimbursed in accordance with Employer's expense reimbursement
policies and guidelines.

            (f) Vacation; Sick Leave. During the Term, Executive shall be
entitled to four weeks (4) weeks vacation per year, paid holidays, sick leave,
and similar benefits, to be earned and used in accordance with Employer's policy
and procedure for other similarly situated senior executive officers.

            (g) Modification. Employer reserves the right to modify, suspend or
discontinue any and all of the above plans, practices, policies and programs
referenced in Sections 3(d) and (e) at any time in its discretion without
recourse by Executive so long as such action is taken generally with respect to
other similarly situated senior executive officers. Any such modification,
suspension or discontinuance of the plans, practices and policies referenced in
Section 3(e) will not apply to otherwise reimbursable expenses incurred by
Executive prior to any such modification, suspension or discontinuance.

            Section 4. Termination of Employment

            (a) Resignation. Executive may voluntarily terminate his employment
with Employer, at any time, with or without Good Reason, upon written notice to
Employer.

            (b) Termination. Employer may terminate Executive's employment at
any time, with or without Cause, upon written notice to Executive.

            (c) Death or Disability. Executive's employment shall terminate
immediately upon Executive's death. In the event Employer, in good faith,
determines that Executive is unable to perform the functions of his position due
to a Disability (as defined below), it may

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notify Executive in writing of its intention to terminate Executive's employment
and Executive's employment with Employer shall terminate effective on the
thirtieth (30th) day after receipt of such notice by Executive. For the purposes
of this Agreement, "Disability" shall mean a physical or mental impairment that
substantially limits a major life activity of Executive and renders Executive
unable to perform the essential functions of his position even with reasonable
accommodation (that does not impose an undue hardship on Employer), and which
has lasted at least (i) sixty (60) consecutive days, (ii) the balance of
Executive's entitlement to leave, if any, under the Family and Medical Leave
Act, or other similar statute or (iii) the balance of any election period under
the Employer's long term disability program (without regard to whether Executive
is awarded benefits under such program), whichever is longer.

            (d) Cause. Employer may immediately terminate Executive's employment
for "Cause" by giving written notice to Executive. For purposes of this
Agreement, "Cause" shall mean:

                  (1)   Executive's commission of an act of fraud or
                        embezzlement upon Employer or any of its affiliates; or

                  (2)   Executive's commission of any willful act intended to
                        injure the reputation, business, or any business
                        relationship of Employer or any of its affiliates; or

                  (3)   Executive is found by a court of competent jurisdiction
                        to have committed a felony; or

                  (4)   the refusal or failure of Executive to perform
                        Executive's duties with Employer in a competent and
                        professional manner that is not cured by Executive
                        within ten (10) business days after a written demand
                        therefor is delivered to Executive by the Board which
                        specifically identifies the manner in which the Board
                        believes that Executive has not substantially performed
                        Executive's duties; provided, further, however, that if
                        the Board, in good faith, determines that the refusal or
                        failure by Executive is egregious in nature or is not
                        susceptible of cure, then no cure period shall be
                        required hereunder; or

                  (5)   the refusal or failure of Executive to comply with any
                        of his material obligations under this Agreement
                        (including any exhibit hereto) that is not cured by
                        Executive within ten (10) business days after a written
                        demand therefor is delivered to Executive by the Board
                        which specifically identifies the manner in which the
                        Board believes Executive has materially breached this
                        Agreement; provided, further, however, that if the
                        Board, in good faith, determines that the refusal or
                        failure by Executive is egregious in nature or is not
                        susceptible of cure, then no cure period shall be
                        required hereunder.

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            (e) Good Reason. Executive may terminate his employment for "Good
Reason," by delivering written notice of such termination ("Employer Default
Notice") to Employer within sixty (60) days of the occurrence of any of the
following events, each of which shall constitute Good Reason: (i) Employer's
material breach of any provision of this Agreement, the Stock Incentive Plans or
any agreements thereunder, which has not been cured within the allotted time;
(ii) a material reduction of Executive's then current title, status, authority,
responsibility or duties or the assignment to Executive of any duties materially
inconsistent with Executive's then current position; (iii) any material
reduction in Executive's salary or benefits; (iv) the failure of any successor
entity to assume the terms of this Agreement upon any Change of Control; (v) the
relocation of Executive to a facility or location more than fifty (50) miles
from Employer's principal offices at the address set forth in the preamble to
this Agreement; or (vi) the failure of Employer to renew this Agreement upon the
expiration of the Initial Term or any Renewal Term. The Employer Default Notice
shall specify the reason for Executive's belief that an event constituting Good
Reason has occurred. Notwithstanding the foregoing, any material breach of this
Agreement by Employer, or other event constituting Good Reason, shall not
constitute Good Reason if any such breach or other event is cured or corrected
by Employer within thirty (30) days following delivery to Employer of the
Employer Default Notice.

            (f) Continuing Obligations. Executive acknowledges and agrees that
any termination under this Section 4 is not intended, and shall not be deemed or
construed, to affect in any way any of Executive's covenants and obligations
contained in Sections 6, 7, and 8 hereof, which shall continue in full force and
effect beyond such termination for any reason.

            Section 5. Termination Obligations

            (a) Resignation. If Executive's employment is terminated voluntarily
by Executive without Good Reason, Executive's employment shall terminate without
further obligations to Executive other than for payment of the sum of any unpaid
Salary determined by the Board and reimbursable expenses and vacation accrued
and owing to Executive prior to the termination. The sum of such amounts shall
hereinafter be referred to as the "Accrued Obligations," which shall be paid to
Executive or Executive's estate or beneficiary within thirty (30) days of the
date of termination. If Executive voluntarily terminates his employment without
Good Reason and within (30) days of such termination, Employer determines that
it would have had Cause to terminate Executive pursuant to Section 4(d),
Executive shall be deemed to have been terminated for Cause and the terms of
Section 5(b) shall apply.

            (b) Cause. If Executive's employment is terminated by Employer for
Cause, this Agreement shall terminate without further obligations to Executive
other than for the timely payment of Accrued Obligations. If it is subsequently
determined by an arbitrator, pursuant to Section 19 hereof, that Employer did
not have Cause for termination, then Employer's decision to terminate shall be
deemed to have been made without Cause and the terms of Section 5(c) shall
apply.

            (c) By Employer Other than for Cause or Death or Disability; By
Executive for Good Reason.

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                  (1) If (A) Employer terminates Executive's employment for a
reason other than Cause, or due to Executive's death or Disability, or (B)
Executive terminates his employment for Good Reason, Employer shall have no
further obligations to Executive other than for (i) the payment of Accrued
Obligations, (ii) severance pay in an amount equal to twenty-four (24) months of
Salary to be paid in equal installments in accordance with Employer's payroll
practices during the period beginning on the Severance Commencement Date (as
defined below) and ending on the 24-month anniversary of the date of the
Executive's termination of employment (the "Date of Termination"); provided,
however, that, notwithstanding the foregoing, if the Severance Commencement Date
is the six-month anniversary of the Date of Termination, then Employer shall, as
of the six-month anniversary of the Date of Termination, pay to the Executive a
lump-sum amount equal to 25% of the Severance Amount (with the other 75% of the
Severance Amount payable to the Executive in equal monthly installments during
the period beginning on the six-month anniversary of the Date of Termination and
ending on the 24-month anniversary thereof), and (iii) a pro rata bonus
calculated based on multiplying the percentage of the year Executive worked for
Employer during the year of his termination by the Bonus received by Executive
during the preceding year and (iv) the reimbursement of premiums otherwise
payable by Executive pursuant to COBRA for a period of up to 12 months, or until
Executive no longer is eligible for COBRA continuation coverage, whichever is
earlier. For purposes of this Section 5, "Severance Commencement Date" shall
mean (x) if any stock of Employer or its affiliates is publicly traded on an
established securities market or otherwise and the Board (or its delegate)
determines in its discretion that as of the Date of Termination the Executive is
a "key employee" (within the meaning of Section 416(i) of the Internal Revenue
Code of 1986, as amended (the "Code")), as interpreted in accordance with
Section 409A of the Code and Department of Treasury regulations and other
interpretive guidance issued thereunder) and that Section 409A of the Code
applies with respect to a payment to the Executive pursuant to Section
5(c)(1)(ii), the six-month anniversary of the Date of Termination; or (y) if the
Board (or its delegate) determines in its discretion that the Executive is not
such a "key employee" as of the Date of Termination (or that Section 409A of the
Internal Revenue Code does not apply with respect to a payment to the Executive
pursuant to Section 5(c)(1)(ii)), the Date of Termination. The payments
described in this Section 5(c)(1), except for those set forth in Section
5(c)(1)(ii) and (iv), shall be made within thirty (30) days of the Date of
Termination.

                  (2) If Executive terminates his employment for Good Reason and
it is subsequently determined by an arbitrator, pursuant to Section 20 hereof,
that Executive did not have Good Reason for termination, then Executive's
decision to terminate for Good Reason shall be deemed to have been a voluntary
resignation, the terms of Section 5(a) shall apply, and all monies paid to
Executive pursuant to this Section 5(c)(1), except for those monies paid
pursuant to Section 5(c)(1)(i), shall be immediately returned to Employer.

                  (3) The amounts payable pursuant to Section 5(c)(1) shall be
the only amounts Executive shall receive for termination in accordance with this
Section 5(c); provided, however, that no amounts shall be payable pursuant to
this section 5(c) on or following the date Executive breaches any of Sections 7,
8 or 9 of this Agreement.

            (d) Mitigation. In the event Executive's employment with Employer is
terminated pursuant to this Section 5, Executive shall be obligated to mitigate
any severance payments due to Executive in accordance with Section 5(c)(1)(ii).
Executive shall be required to

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notify Employer, in writing, within seven (7) days of obtaining subsequent
employment by an unrelated party, which shall include, without limitation,
self-employment, consulting or other arrangement, but not passive investment
activities. In the event Executive obtains other employment during any severance
payout period described in Section 5(c)(1)(ii), the severance payments due to
Executive thereunder shall be reduced to an amount equal to the lesser of (i)
fifty (50%) percent of Executive's Salary immediately prior to the Date of
Termination or (ii) fifty (50%) percent of Executive's base compensation
received for subsequent employment, self-employment, consulting or other
arrangement, commencing on the date Executive commences providing services in
his new capacity. Nothing herein shall require Executive to seek employment,
self-employment, consulting or other arrangement.

            (e) Release. Notwithstanding anything to the contrary contained
herein, no severance payments required hereunder shall be made by Employer until
such time as Executive shall execute a general release for the benefit of
Employer and its affiliates in a form satisfactory to Employer. Such general
release shall not apply to (i) Executive's rights under any Stock Incentive Plan
award agreements or (ii) Executive's rights, as applicable, to indemnification
under Employer's charter or bylaws, any indemnification agreement or applicable
law.

            (f) Equity Compensation Awards. Except as expressly provided herein,
except for the provisions of Section 3(c) of this Agreement, the terms of the
Stock Incentive Plans and any related award agreements and/or notice of grant
shall govern the termination, vesting, and/or exercise of Executive's stock
options or other equity awards upon the termination of Executive's employment
for any reason.

            (g) Exclusive Remedy. Executive agrees that the payments set forth
in this Agreement shall constitute the exclusive and sole remedy for any
termination of Executive's employment and Executive covenants not to assert or
pursue any other remedies, at law or in equity, with respect to this Agreement.

            (h) Termination of Executive's Office. Following the termination of
Executive's employment for any reason, Executive shall hold no further office or
position with Employer or any of its affiliates.

            Section 6. Parachute Payments.

            (a) If it is determined by a nationally recognized United States
public accounting firm selected by the Employer and approved in writing by the
Executive (which approval shall not be unreasonably withheld) (the "Auditors")
that any payment or benefit made or provided to the Executive in connection with
this Agreement or otherwise (including without limitation any Stock Option or
other equity based award vesting) (collectively, a "Payment"), would be subject
to the excise tax imposed by Section 4999 of the Code (the "Parachute Tax"),
then the Employer shall pay to the Executive, prior to the time the Parachute
Tax is payable with respect to such Payment, an additional payment (a "Gross-Up
Payment") in an amount such that, after payment by the Executive of all taxes
(including any Parachute Tax) imposed upon the Gross-Up Payment, the Executive
retains an amount of the Gross-Up Payment equal to the Parachute Tax imposed
upon the Payment. The amount of any Gross-Up Payment shall be determined by the
Auditors, subject to adjustment, as necessary, as a result of any Internal

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Revenue Service position. For purposes of making the calculations required by
this Agreement, the Auditors may make reasonable assumptions and approximations
concerning applicable taxes and may rely on reasonable, good faith
interpretations concerning the application of Sections 280G and 4999 of the
Code, provided that the Auditors' determinations must be made with substantial
authority (within the meaning of Section 6662 of the Code).

            (b) The federal tax returns filed by the Executive (and any filing
made by a consolidated tax group which includes the Employer) shall be prepared
and filed on a basis consistent with the determination of the Auditors with
respect to the Parachute Tax payable by the Executive. The Executive shall make
proper payment of the amount of any Parachute Tax, and at the request of the
Employer, provide to the Employer true and correct copies (with any amendments)
of his federal income tax return as filed with the Internal Revenue Service, and
such other documents reasonably requested by the Employer, evidencing such
payment. If, after the Employer's payment to the Executive of the Gross-Up
Payment, the Auditors determine in good faith that the amount of the Gross-Up
Payment should be reduced or increased, or such determination is made by the
Internal Revenue Service, then within ten (10) business days of such
determination, the Executive shall pay to the Employer the amount of any such
reduction, or the Employer shall pay to the Executive the amount of any such
increase; provided, however, that in no event shall the Executive have any such
refund obligation if it is determined by the Employer that to do so would be a
violation of the Sarbanes-Oxley Act of 2002, as it may be amended from time to
time; and provided, further, that if the Executive has prior thereto paid such
amounts to the Internal Revenue Service, such refund shall be due only to the
extent that a refund of such amount is received by the Executive; and provided,
further, that (i) the fees and expenses of the Auditors (and any other legal and
accounting fees) incurred for services rendered in connection with the Auditor's
determination of the Parachute Tax or any challenge by the Internal Revenue
Service or other taxing authority relating to such determination shall be paid
by the Employer and (ii) the Employer shall indemnify and hold the Executive
harmless on an after-tax basis for any interest and penalties imposed upon the
Executive to the extent that such interest and penalties are related to the
Auditor's determination of the Parachute Tax or the Gross-Up Payment.
Notwithstanding anything to the contrary herein, the Executive's rights under
this Section 6 shall survive the termination of his employment for any reason
and the termination or expiration of this Agreement for any reason.

            Section 7. Restrictions Respecting Confidential Information

            Executive hereby covenants and agrees that, during his employment
and thereafter, Executive will not, under any circumstance, disclose in any way
any Confidential Information (as defined below) to any other person other than
(i) at the direction of and for the benefit of Employer, (ii) to his attorney or
other advisers in connection with Executive's enforcement of his rights
hereunder, provided such individuals or entities agree to be bound by the
confidentiality restrictions herein contained, and if such Confidential
Information is relevant to such enforcement action, to the court or arbitrator,
as applicable, subject to a protective order. For the purposes of the foregoing,
"Confidential Information" means any information pertaining to the assets,
business, creditors, vendors, manufacturers, customers, data, employees,
financial condition or affairs, formulae, licenses, methods, operations,
procedures, reports, suppliers, systems and technologies of Employer and its
affiliates, including (without limitation) the contracts, patents, trade secrets
and customer lists developed or otherwise acquired by Employer

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and its affiliates; provided, however, that Confidential Information shall
exclude any information that was, is, or becomes publicly available other than
through disclosure by Executive or any other person known to Executive to be
subject to confidentiality obligations to Employer. All Confidential Information
is and will remain the sole and exclusive property of Employer and its
affiliates. Following the termination of his employment, Executive shall return
all documents and other tangible items containing Confidential Information to
Employer, without retaining any copies, notes or excerpts thereof.

            Section 8. Proprietary Matters

            Executive expressly understands and agrees that any and all
improvements, inventions, discoveries, processes, or know-how that are generated
or conceived by Executive during the Term (collectively, the "Inventions") will
be the sole and exclusive property of Employer, and Executive will, whenever
requested to do so by Employer (either during the Term or thereafter), execute
and assign any and all applications, assignments and/or other instruments and do
all things which Employer may deem necessary or appropriate in order to apply
for, obtain, maintain, enforce and defend patents, copyrights, trade names or
trademarks of the United States or of foreign countries for said Inventions, or
in order to assign and convey or otherwise make available to Employer the sole
and exclusive right, title, and interest in and to said Inventions,
applications, patents, copyrights, trade names or trademarks; provided, however,
that the provisions of this Section 8 shall not apply to an Invention that
Executive developed entirely on his own time without using Employer's
Confidential Information except for those Inventions that either (i) directly
and materially relate, at the time of conception or reduction to practice of the
invention, to Employer's business, or actual or demonstrably anticipated
research or development of Employer, or (ii) directly and materially result from
any work performed by Executive for Employer. Executive shall promptly
communicate and disclose to Employer all Inventions conceived, developed or made
by him during his employment by Employer, whether solely or jointly with others,
and whether or not patentable or copyrightable, (a) which relate to any matters
or business of the type carried on or being developed by Employer, or (b) which
result from or are suggested by any work done by him in the course of his
employment by Employer. Executive shall also promptly communicate and disclose
to Employer all material other data obtained by him concerning the business or
affairs of Employer in the course of his employment by Employer.

            Section 9. Nonsolicitation/Non-Compete

            (a) Executive agrees that throughout his employment and for a period
of two (2) years following the termination of his employment for any reason, he
will not directly or indirectly, own, manage, operate, control, or participate
in the ownership, management, operation, or control of, or be connected with, or
have any financial interest in, any Competitor. Ownership, for personal
investment purposes only, of not to exceed (i) individually, two (2%) percent of
the outstanding capital stock of any privately held entity, or (ii) voting stock
of any publicly held corporation shall not constitute a violation hereof. For
purposes of this Agreement, the term "Competitor" shall mean any individual or
entity, present or future, then providing any of the following products or
services: (1) a multi-finance source automotive finance portal, (2) electronic
contracting for automotive finance or lease transactions, other than at a
financing source entity that purchases electronic contracts or leases from
automotive dealers, (3)

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<PAGE>

automotive lease, retail and/or balloon payment comparison or desking tools or
(4) any other sales or finance and insurance-related products or services for
automotive dealerships similar to any products or services offered by Employer
or any of its affiliates.

            (b) Executive agrees that during his employment with Employer and
for a period of two (2) years following the termination of his employment for
any reason, he will not actively solicit for employment, consulting or any other
arrangement any employee of Employer or any of its present or future affiliates
(while an affiliate).

            (c) Executive agrees that during his employment with Employer and
for a period of two (2) years following the termination of his employment for
any reason, he will not influence or attempt to influence customers of Employer
or any of its present or future affiliates, either directly or indirectly, to
divert their business to any Competitor.

            (d) The restrictions contained in this Section 9 are necessary for
the protection of the business and goodwill of Employer and are considered by
Executive to be reasonable for such purpose. Further, Executive represents that
these restrictions will not prevent him from earning a livelihood during the
restricted period.

            (e) This Section 9 shall survive the termination or expiration of
this Agreement.

            Section 10. Equitable Relief

            Executive acknowledges and agrees that Employer will suffer
irreparable damage which cannot be adequately compensated by money damages in
the event of a breach, or threatened breach, of any of the terms and provisions
of Sections 7, 8 and 9 of this Agreement, and that, in the event of any such
breach, or threatened breach, Employer will not have an adequate remedy at law.
It is therefore agreed that Employer, in addition to all other such rights,
powers, privileges and remedies that it may have, shall be entitled to
injunctive relief, specific performance or such other equitable relief as
Employer may request to enforce any of those terms and provisions and to enjoin
or otherwise restrain any act prohibited thereby, and Executive will not raise
and hereby waives any objection or defense that there is an adequate remedy
available at law. Notwithstanding the provisions of Section 20 of this
Agreement, Executive agrees that Employer shall be entitled to seek such
injunctive relief, without bond, in a court of competent jurisdiction and
Executive hereby consents to the jurisdiction of the state and federal courts of
New York for purposes of such an action. Executive agrees that any claim he may
have against Employer or any of its affiliates shall not constitute a defense
against the issuance of any such equitable relief. The foregoing shall not
constitute a waiver of any of Employer's rights, powers, privileges and remedies
against or in respect of a breaching party or any other person or thing under
this Agreement, or applicable law.

            Section 11. Notice

            Any notice, request, demand or other communication hereunder shall
be in writing, shall be delivered by hand or sent by registered or certified
mail or by reputable overnight delivery service, postage prepaid, to the
addressee at the address set forth below (or at

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<PAGE>

such other address as shall be designated hereunder by written notice to the
other party hereto) and shall be deemed conclusively to have been given when
actually received by the addressee.

            All notices and other communications hereunder shall be addressed as
follows:

                  If to Executive at the address set forth in the Employer's
                  payroll records.

                  If to Employer:

                  DealerTrack Holdings, Inc.
                  1111 Marcus Avenue, Suite M04
                  Lake Success, NY 11042

                  With a copy to:

                  General Counsel
                  DealerTrack Holdings, Inc.
                  1111 Marcus Avenue, Suite M04
                  Lake Success, NY 11042

                  and to:

                  Latham & Watkins LLP
                  885 Third Avenue
                  New York, NY  10022
                  Attention: Bradd L. Williamson, Esq.

or to such other address as either party shall have furnished to the other in
writing in accordance herewith.

            Section 12. Legal Counsel

            In entering into this Agreement, the parties represent that they
have relied upon the advice of their attorneys, who are attorneys of their own
choice, and that the terms of this Agreement have been completely read and
explained to them by their attorneys, and that those terms are fully understood
and voluntarily accepted by them.

            Section 13. Section and Other Headings

            The section and other headings contained in this Agreement are for
reference purposes only and shall not affect the meaning or interpretation of
this Agreement.

            Section 14. Governing Law

            This Agreement has been executed and delivered, and shall be
governed by and construed in accordance with the applicable laws pertaining, in
the State of New York, without regard to conflicts of laws principles.

                                       12
<PAGE>

            Section 15. Severability

            In the event that any term or provision of this Agreement shall be
finally determined to be superseded, invalid, illegal or otherwise unenforceable
pursuant to applicable law by a governmental authority having jurisdiction and
venue, that determination shall not impair or otherwise affect the validity,
legality or enforceability, to the maximum extent permissible by law, (a) by or
before that authority of the remaining terms and provisions of this Agreement,
which shall be enforced as if the unenforceable term or provision were deleted,
or (b) by or before any other authority of any of the terms and provisions of
this Agreement.

            Section 16. Counterparts

            This Agreement may be executed in two counterpart copies of the
entire document or of signature pages to the document, each of which may be
executed by one of the parties hereto, but all of which, when taken together,
shall constitute a single agreement binding upon both of the parties hereto.

            Section 17. Benefit

            This Agreement shall be binding upon and inure to the benefit of the
respective parties hereto and their legal representatives, successors and
assigns. Insofar as Executive is concerned, this Agreement, being personal,
cannot be assigned; provided, however, that should Executive become entitled to
payment pursuant to Section 5 hereof, he may assign his rights to such payment
to his legal representatives, successors, and assigns. Without limiting the
generality of the foregoing, all representations, warranties, covenants and
other agreements made by or on behalf of Executive in this Agreement shall inure
to the benefit of the successors and assigns of Employer.

            Section 18. Modification

            This Agreement may not be amended or modified other than by a
written agreement executed by all parties hereto.

            Section 19. Entire Agreement

            Except as provided in Section 5(f) hereof, this Agreement contains
the entire agreement of the parties and supersedes all other representations,
warranties, agreements and understandings, oral or otherwise, among the parties
with respect to the matters contained herein, including any prior employment
agreements between Executive and Employer or any affiliate of Employer.

            Section 20. Arbitration

            (a) Executive agrees that any dispute or controversy arising out of,
relating to, or in connection with this Agreement or the termination thereof, or
the interpretation, validity, construction, performance, breach, or termination
thereof, shall be settled by expedited, binding arbitration to be held in New
York, New York in accordance with the National Rules for the Resolution of
Employment Disputes then in effect of the American Arbitration Association (the

                                       13
<PAGE>

"Rules"). The arbitrator may grant injunctions or other relief in such dispute
or controversy. The decision of the arbitrator shall be final, conclusive and
binding on the parties to the arbitration. Judgment may be entered on the
arbitrator's decision in any court having jurisdiction. The arbitrator may award
the prevailing party its reasonable attorney's fees.

            (b) The arbitrator shall apply New York law to the merits of any
dispute or claim, without reference to rules of conflicts of law. The
arbitration proceedings shall be governed by federal arbitration law and by the
Rules, without reference to state arbitration law.

            (c) EXECUTIVE HAS READ AND UNDERSTANDS THIS SECTION, WHICH DISCUSSES
ARBITRATION. EXECUTIVE UNDERSTANDS THAT BY SIGNING THIS AGREEMENT, EXECUTIVE IS
AGREEING TO SUBMIT ANY CLAIMS ARISING OUT OF, RELATING TO, OR IN CONNECTION WITH
THIS AGREEMENT, OR THE INTERPRETATION, VALIDITY, CONSTRUCTION, PERFORMANCE,
BREACH OF TERMINATION THEREOF, TO BINDING ARBITRATION, AND THAT THIS ARBITRATION
CLAUSE CONSTITUTES A WAIVER OF EXECUTIVE'S RIGHT TO A JURY TRIAL AND RELATES TO
THE RESOLUTION OF ALL DISPUTES RELATING TO ALL ASPECTS OF THE EMPLOYER/EMPLOYEE
RELATIONSHIP INCLUDING, BUT NOT LIMITED TO, STATUTORY DISCRIMINATION CLAIMS.

            Section 21. Representations and Warranties of Executive

            In order to induce Employer to enter into this Agreement, Executive
represents and warrants to Employer, to the best of his knowledge after the
review of his personnel files, that: (a) the execution and delivery of this
Agreement by Executive and the performance of his obligations hereunder will not
violate or be in conflict with any fiduciary or other duty, instrument,
agreement, document, arrangement or other understanding to which Executive is a
party or by which he is or may be bound or subject; and (b) Executive is not a
party to any instrument, agreement, document, arrangement or other understanding
with any person (other than Employer) requiring or restricting the use or
disclosure of any confidential information or the provision of any employment,
consulting or other services.

            Section 22. Waiver of Breach

            Except as may specifically provided herein, the failure of a party
to insist on strict adherence to any term of this Agreement on any occasion
shall not be considered a waiver or deprive that party of the right thereafter
to insist upon strict adherence to that term or any term of this Agreement. Any
waiver hereto must be in writing.

            Section 23. Section 409A.

            The parties acknowledge and agree that, to the extent applicable,
this Agreement shall be interpreted in accordance with Section 409A of the Code
and Department of Treasury regulations and other interpretive guidance issued
thereunder, including without limitation any such regulations or other guidance
that may be issued after the Effective Date. Notwithstanding any provision of
this Agreement to the contrary, in the event that Employer determines that any
amounts payable hereunder will be immediately taxable to the Executive under
Section 409A of the Code and related Department of Treasury guidance, Employer
may (a) adopt such

                                       14
<PAGE>

amendments to this Agreement and appropriate policies and procedures, including
amendments and policies with retroactive effect, that Employer determines
necessary or appropriate to preserve the intended tax treatment of the benefits
provided by this Agreement and/or (b) take such other actions as Employer
determines necessary or appropriate to comply with the requirements of Section
409A of the Code and related Department of Treasury guidance, including such
Department of Treasury guidance and other interpretive materials as may be
issued after the Effective Date.

                            [signature page follows]

                                       15
<PAGE>

            IN WITNESS WHEREOF, the parties hereto have executed and delivered
this Agreement as of the date first written above.

                                EXECUTIVE:

                                Mark F. O'Neil

                                EMPLOYER:

                                DEALERTRACK HOLDINGS, INC.

                                By: ___________________________________________

                                Name: Eric D. Jacobs

                                Title: Senior Vice President, General Counsel &
                                       Secretary