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                                                                   EXHIBIT 10.21

                        RESTRICTED UNIT AWARD AGREEMENT

      This instrument is issued as of the 19th day of January, 2006, by ONEOK,
Inc., an Oklahoma corporation, (hereinafter referred to as "Corporation"), to
<<OFFICER_NAME>> (hereinafter referred to as "Grantee"), an employeE of the
Corporation or a division or subsidiary thereof, pursuant to the terms of the
ONEOK, Inc. Equity Compensation Plan, effective February 17, 2005, (hereinafter
referred to as the "Plan").

      1. Restricted Unit Award. This instrument and that certain Notice of
Restricted Unit Award and Agreement, dated January 19, 2006, a copy of which is
attached hereto and incorporated herein by reference (the "Notice of Restricted
Unit Award and Agreement") constitute evidence of the issuance and grant of a
Restricted Unit Award to the Grantee by the Corporation under the Plan of
<<NO_OF_RESTRICTED_UNITS>> Restricted Units that shall entitle thE Grantee to
receive shares of the Corporation's Common Stock (hereinafter referred to as
"Common Stock") all subject to the terms, provisions, and conditions of this
instrument (including, without limitation, the restrictions stated in paragraph
5, below) and of the Plan, which are incorporated herein by reference
(hereinafter referred to as "Award"). This instrument, when executed by the
Grantee, together with the Notice of Restricted Unit Award and Agreement
constitute an agreement between the Corporation and the Grantee. Notwithstanding
the foregoing, should there be any inconsistency between the provisions of this
instrument and the terms of the Award stated in the resolutions and records of
the Board of Directors of the Corporation, or the Plan, the provisions of such
resolutions and records and of the Plan shall control. The grant of Restricted
Units to the Grantee shall be effective in the manner and to the extent provided
in this instrument and the Plan as to all or any part of the shares of Common
Stock subject to the grant from time to time during the period stated herein.

      2. Plan. The Award is issued pursuant to the Plan, as approved by the
Shareholders of the Corporation, which provides that a specific aggregate number
of shares of Common Stock of the Corporation may be issued or transferred
pursuant to Stock Incentives under the Plan. The Plan specifies the authority of
the Corporation, its Board of Directors, and a committee of the Board of
Directors to select employees to be granted Stock Incentives. The Executive
Compensation Committee of the Board of Directors (hereinafter referred to as the
"Committee") is authorized to administer the Plan with respect to the Award and
the grant of the Award made to the Grantee pursuant to the Plan. Except where
expressly stated or clearly indicated otherwise by the terms of this instrument,
all terms, words and phrases used herein shall have the same meaning and effect
as stated in the Plan. The Grantee has been provided a complete copy of the Plan
with this instrument.

      3. Grantee's Agreement Concerning Award and Employment. In consideration
of the Corporation's granting the Award of Restricted Units as incentive
compensation to Grantee pursuant to this instrument, the Grantee by acceptance
thereof, and signing this instrument evidencing its terms, agrees to such terms
and to continue to contribute and perform service in the employ of the
Corporation or a division or subsidiary thereof at the direction, will and
pleasure of the Corporation and the Board of Directors. Provided, however,
neither the foregoing agreement of the Grantee in this paragraph 3, nor any
other provision in the Plan shall

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confer on the Grantee any right to continue in the employ of the Corporation (or
a division or subsidiary thereof), or interfere in any way with the right of the
Corporation (or such division or subsidiary) to terminate the Grantee's
employment at any time.

      4. Registration of Stock; Grantee's Representation With Respect To
Acquiring for Investment. It is intended by the Corporation that the Plan and
shares of Common Stock covered by the Award issued and granted to the Grantee
referred to in paragraph 1, above, are to be registered under the Securities Act
of 1933, as amended, prior to the date of the grant; provided, that in the event
such registration is for any reason not made effective for such shares, the
Grantee agrees, for the Grantee, and for the Grantee's heirs and legal
representatives by inheritance or bequest, that all shares acquired pursuant to
the grant will be acquired for investment and not with a view to, or for sale or
tender in connection with the distribution of any part thereof, including any
transfer or distribution of such shares by the Grantee pursuant to the grant and
this instrument or as otherwise allowed by the Plan.

      5. Restrictions; Restricted Period; Transfer of Common Stock to Grantee.
The issue and grant of the Award to the Grantee stated in paragraph 1, above,
are subject to the following terms and conditions:

            (a) The ownership and transfer of the Restricted Units granted to
the Grantee shall be restricted during the period beginning January 19, 2006,
the date of the grant thereof (hereinafter referred to as "Grant Date") and
ending on January 19, 2009, (which period is hereinafter referred to as
"Restricted Period"), as herein provided.

            (b) The Restricted Units, or any Common Stock or cash to be paid or
transferred to Grantee pursuant to the Award may not be sold, assigned,
transferred, pledged, encumbered or otherwise disposed of by Grantee or any
other person except as provided in this instrument and the Plan until the
expiration of the Restricted Period.

            (c) The Grantee shall earn and become vested and entitled to the
Restricted Units granted by this Award under paragraph 1, above, at the
expiration of the Restricted Period. Upon expiration of the Restricted Period,
the Grantee shall be entitled to receive, and the Corporation shall issue to
Grantee one (1) share of Common Stock for each Restricted Unit that becomes
earned by and vested in the Grantee pursuant to the Award.

            (d) The Grantee shall become vested in the Restricted Units granted
to the Grantee hereunder and Common Stock paid and transferred pursuant to the
Award free and clear of all restrictions imposed by the Award if the Grantee's
employment by the Corporation (or a division or Subsidiary thereof) does not
terminate during the Restricted Period; provided, that the Grantee shall become
partially vested in the Restricted Units and Common Stock payable pursuant to
the Award and the restrictions imposed by the Award shall partially cease to
apply in certain events to the extent described in paragraph 6(d), below.

            (e) If the Grantee's employment with the Corporation (or a division
or Subsidiary thereof) terminates prior to the end of the Restricted Period by
reason of (i) the Grantee's voluntary termination of the Grantee's employment
with the Corporation (or a division or Subsidiary), or (ii) the involuntary
Termination for Cause by the Corporation of the Grantee's

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employment with the Corporation (or a division or Subsidiary), the Grantee shall
forfeit all the Grantee's right, title or interest in the Restricted Units, and
to any Common Stock payable pursuant to the Award; and the Grantee shall forfeit
such right, title and interest in the Restricted Units, and to any Common Stock
payable pursuant to the Award regardless of the reason for such termination of
employment. Any such termination of employment of the Grantee described in the
preceding sentence shall not be deemed to occur by reason of transfer of
employment of the Grantee by or between the Corporation and any division or
Subsidiary of the Corporation.

            (f) The Grantee shall not be entitled to vote any shares of Common
Stock that may be issued to the Grantee pursuant to the Award prior to the end
of the Restricted Period and actual issuance of such Common Stock to the Grantee
pursuant to the Award.

            (g) No dividends with respect to shares of Common Stock that may be
issued to the Grantee under the Award shall accrue or become payable to the
Grantee prior to the end of the Restricted Period and issuance of such Common
Stock to Grantee pursuant to the Award.

      6. Transferability of Restricted Units, Cash or Common Stock; Termination
of Employment.

            (a) Except as provided in subparagraph (b) of this paragraph 6,
below, this instrument, the Grantee's rights and obligations hereunder, and the
Restricted Units granted hereunder shall not be transferable by the Grantee
otherwise than by will or the laws of descent and distribution which apply to
the Grantee's estate.

            (b) Notwithstanding the foregoing, the Grantee may transfer any part
or all of the Grantee's rights in the Restricted Units to members of the
Grantee's immediate family, or to one or more trusts for the benefit of such
immediate family members, or partnerships in which such immediate family members
are the only partners if the Grantee does not receive any consideration for the
transfer. In the event of any such transfer, Restricted Units shall continue to
be subject to the same terms and conditions otherwise applicable hereunder and
under the Plan immediately prior to its transfer, except that such rights shall
not be further transferable by the transferee inter vivos, except for transfer
back to the original Grantee. For any such transfer to be effective, the Grantee
must provide prior written notice thereof to the Committee, unless otherwise
authorized and approved by the Committee, in its sole discretion; and the
Grantee shall furnish to the Committee such information as it may request with
respect to the transferee and the terms and conditions of any such transfer. For
purposes of transfer of this grant under this subparagraph (b), "immediate
family" shall mean the Grantee's spouse, children and grandchildren.

            (c) Notwithstanding anything to the contrary expressed or implied
herein (including without limitation, the restrictions stated in paragraph 5,
above, applicable to the Restricted Units), all rights and interest of the
Grantee in the Restricted Units shall become invalid and wholly terminated and
forfeited upon (i) the Grantee's voluntary termination of the Grantee's
employment with the Corporation (or a division or Subsidiary), or (ii) the
involuntary Termination for Cause by the Corporation of the Grantee's employment
with the Corporation (or a division or Subsidiary).

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            (d) Notwithstanding the foregoing provisions, in the event of
termination of the Grantee's employment with the Corporation (or a division or
Subsidiary) during the Restricted Period by reason of (i) the involuntary
termination of the Grantee's employment with the Corporation (or a division or
Subsidiary) other than a Termination for Cause (ii) the retirement of the
Grantee, (iii) the Total Disability of the Grantee, or (iv) the Grantee's death
while still employed by the Corporation (or a division or Subsidiary), then
partial vesting shall be allowed as provided in this paragraph 6(d) and the
Grantee shall become vested in and receive, in the event of any such involuntary
termination of employment other than a Termination for Cause, retirement or
Total Disability, and the legatees, or personal representatives or heirs of the
Grantee shall be vested in and entitled to receive, in the event of the
Grantee's death, the percentage of the Restricted Units which is determined by
dividing the number of full months which have elapsed under the Restricted
Period at the time of such termination of employment by the number of full
months in the Restricted Period.

            (e) The Grantee may designate a Beneficiary to receive any rights of
the Grantee which may become vested in the event of the death of the Grantee
under procedures and in the form established by the Committee; and in the
absence of such designation of a beneficiary, any such rights shall be deemed to
be transferred to the estate of the Grantee.

            (f) For purposes of the Award to the Grantee and this instrument, an
involuntary "Termination for Cause" of the Grantee's employment with and by the
Corporation (or a division or Subsidiary) shall mean that the Corporation (or a
division or Subsidiary) has terminated such employment by reason of (i) the
Grantee's conviction in a court of law of a felony, or any crime or offense
involving misuse or misappropriation of money or property, (ii) the Grantee's
violation of any covenant, agreement or obligation not to disclose confidential
information regarding the business of the Corporation (or a division or
Subsidiary), (iii) any violation by the Grantee of any covenant not to compete
with the Corporation (or a division or Subsidiary), (iv) any act of dishonesty
by the Grantee which adversely effects the business of the Corporation (or a
division or Subsidiary), (v) any willful or intentional act of the Grantee which
adversely affects the business of, or reflects unfavorably on the reputation of
the Corporation (or a division or Subsidiary); (vi) the Grantee's use of alcohol
or drugs which interferes with the Grantee's performance of duties as an
employee of the Corporation (or a division or Subsidiary), or (vii) the
Grantee's failure or refusal to perform the specific directives of the
Corporation's Board of Directors, or its officers which directives are
consistent with the scope and nature of the Grantee's duties and
responsibilities with the existence and occurrence of all of such causes to be
determined by the Corporation, in its sole discretion; provided, that nothing
contained in the foregoing provisions of this paragraph shall be deemed to
interfere in any way with the right of the Corporation (or a division or
Subsidiary), which is hereby acknowledged, to terminate the Grantee's employment
at any time without cause.

            (g) For purposes of this instrument and the Award, "Total
Disability" shall mean that the Grantee is permanently and totally disabled and
unable to engage in any substantial gainful activity by reason of a medically
determinable physical or mental impairment which can be expected to result in
death or which has lasted or can be expected to last for a continuous period of
not less than twelve (12) months, and has established such disability to the
extent and in the manner and form as may be required under the provisions of
Section 22(e) of

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the Internal Revenue Code of 1986, as amended (or corresponding section of any
future federal tax code), and regulations thereunder.

      7. Administration of Restricted Unit Award. The grant of the Award shall
be subject to such other rules and requirements as the Committee, in its sole
discretion, may determine to be appropriate with respect to administration
thereof and the restrictions made applicable to the Grantee and the Restricted
Units during the Restricted Period. This instrument and the rights and
obligations of the parties involved, shall be subject to interpretation and
construction by the Committee to the same extent and with the same effect as the
Committee actions under pertinent provisions of the Plan. The Grantee shall take
all actions and execute and deliver all documents as may from time to time be
requested by the Committee in connection with such restrictions and in
furtherance hereof. The Grantee agrees to pay to the Corporation any applicable
federal, state, or local income, employment, social security, medicare, or other
withholding tax obligation arising in connection with the grant of the Award to
the Grantee; and the Corporation shall have the right, without the Grantee's
prior approval or direction, to satisfy such withholding tax by withholding all
or any part of the Common Stock that would otherwise be transferred and
delivered to the Grantee, with any shares of Common Stock so withheld to be
valued at the Fair Market Value (as defined in the Plan) on the date of such
withholding. The Grantee, with the consent of the Corporation, may satisfy such
withholding tax by delivery and transfer to the Corporation of shares of Common
Stock previously owned by the Grantee, with any shares so delivered and
transferred to be valued at the Fair Market Value on the date of such delivery.

      8. Adjustment Provisions. It is understood that, prior to the expiration
of the Restricted Period, certain changes in capitalization of the Corporation
may occur. It is, therefore, understood and agreed with respect to changes in
capitalization that:

            (a) If a stock dividend is declared on the Common Stock of the
Corporation, there shall be added to the number of Restricted Units described in
paragraph 1 of this instrument, the number of Restricted Units which the Grantee
would have been entitled to if the Grantee had been the fully vested and
unrestricted owner of the number of Restricted Units then held under the Award
granted, but not theretofore received without restriction; provided, however,
that the additional Restricted Units shall be subject to all terms and
provisions of this instrument (including, without limitation, the restrictions
stated in paragraph 5, above), and in making such adjustments, no fractional
Restricted Units shall be awarded, and the Grantee shall be entitled to receive
only the number of full Restricted Units to which the Grantee may be entitled by
reason of such adjustment at the adjusted grant price per share.

            (b) In the event of an increase in the outstanding shares of Common
Stock of the Corporation, effectuated for the purpose of acquiring properties or
securities of another corporation or business enterprise, there shall be no
increase in the number of shares of Restricted Units which are the subject
matter of the Award evidenced by this instrument as a result of such
acquisition.

            (c) In the event of an increase or decrease in the number of
outstanding shares of Common Stock of the Corporation through recapitalization,
reclassification, stock split-ups, consolidation of shares, changes in par value
and the like, an appropriate adjustment shall be made in the number of
Restricted Units described in paragraph 1 of this instrument, by

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increasing or decreasing the number of Restricted Units, as may be required to
enable the Grantee to acquire the same proportionate stockholdings as the grant
of the Award would originally have provided. Provided, however, that any
additional Restricted Units shall be subject to all terms and provisions of this
instrument (including, without limitation, the restrictions stated in paragraph
5, above), and that in making such adjustments, no fractional Restricted Units
shall be awarded, and the Grantee shall be entitled to receive only the number
of full Restricted Units to which the Grantee may be entitled by reason of such
adjustment.

            (d) Notwithstanding any provision to the contrary stated herein, to
the extent Restricted Units are still restricted and not vested in Grantee at
the time of a Change in Control with respect to the Corporation, then pursuant
to the provisions of the Plan, they shall become fully vested and completely
unrestricted and free and clear of any restrictions stated herein at that time;
provided, that if such Change in Control occurs less than six (6) months after
the date of the grant of Restricted Units to the Grantee, then Restricted Units
shall become fully vested and completely unrestricted and free and clear of any
restrictions stated herein at the time of such Change in Control only if the
Grantee agrees in writing, if requested by the Corporation in writing, to remain
in the employ of the Corporation or a division or subsidiary of the Corporation
at least through the date which is six (6) months after the date the grant was
made with substantially the same title, duties, authority, reporting
relationships, and compensation as on the day immediately preceding the Change
in Control. The provisions of this subparagraph (d) shall be applied in addition
to, and shall not reduce, modify, or change any other obligation or right of the
Grantee otherwise provided for in paragraph 3, above, concerning the Grantee's
continued employment with the Corporation or the termination thereof. If the
Restricted Units become subject to this subparagraph (d), they shall become
fully vested in the Grantee and nonforfeitable. Such Restricted Units are
subject to the provisions of the Plan authorizing the Corporation, or a
committee of its Board of Directors, to provide in advance or at the time of a
Change in Control for cash to be paid in settlement of the Restricted Units, all
subject to such terms and conditions as the Corporation or the Committee, in its
sole discretion, may determine and impose. For purposes of this subparagraph
(d), the term "Change in Control" shall have the same meaning as provided in the
definition of that term stated in the Plan, including any amendments thereof
which may be made from time to time in the future pursuant to the provisions of
the Plan, with any amended definition of such term to apply to all events
thereafter coming within the amended meaning.

      9. Stock Reserved. The Corporation shall at all times during the term of
the Award reserve and keep available such number of shares of its Common Stock
as will be sufficient to satisfy the Award issued and granted to Grantee and the
terms stated in this instrument, and shall pay all original issue taxes, if any,
on the transfer of the Common Stock to the Grantee and all other fees and
expenses necessarily incurred by the Corporation in connection therewith.

      10. Rights of Shareholder. Except as otherwise provided in this
instrument, the Grantee shall have no rights as a shareholder of the Corporation
in respect of the Restricted Units or Common Stock for which the Award is
granted; and the Grantee shall not be considered or treated as a record owner of
shares of Common Stock with respect to the Restricted Units until the Common
Stock is issued to Grantee and no longer subject to any of the restrictions
imposed under the Award indicated in this instrument, and Common Stock is
actually issued and transferred to Grantee.

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      11. Entire Agreement. This instrument contains the entire terms of the
Award, and may not be changed orally or other than by a written instrument
issued and approved by the Corporation pursuant to the Plan. This instrument
supersedes any agreements or understandings that may have previously existed,
and there are no other agreements or understandings, relating to its subject
matter.

      12. Successors and Assigns. The Award evidenced by this instrument shall
inure to the benefit of and be binding upon the heirs, legatees, legal
representatives, successors, and assigns of the parties hereto.

      The Grantee hereby acknowledges receipt of this instrument, the Notice of
Restricted Unit Award Agreement and a copy of the Plan, and accepts the Award
under the terms and conditions stated in this instrument, subject to all terms
and provisions of the Plan, by signing this instrument in duplicate originals,
as of the date first stated above.

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Date                                 <<Officer_Name>>
                                     Grantee

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