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                                                                   Exhibit 10.10

                                   AGREEMENT

This Agreement (this "AGREEMENT") is entered into as of March 5, 2003, by and
among Nextel Communications, Inc., a Delaware corporation (the "COMPANY"),
Digital Radio, L.L.C., a Washington limited liability company ("INVESTOR") and
Craig O. McCaw ("INDIVIDUAL").

Unless the context otherwise requires, terms that are capitalized and not
otherwise defined in context have the meanings set forth in Article 5 of this
Agreement.

                                    RECITALS

A. On April 4, 1995, the Company, Investor and Individual entered into the
Securities Purchase Agreement (as amended through the date hereof, the "SPA").

B. Pursuant to the SPA, on July 28,1995, Investor purchased, among other things,
shares of Class A Convertible Redeemable Preferred Stock of the Company ("CLASS
A PREFERRED STOCK") and shares of Class B Convertible Preferred Stock of the
Company ("CLASS B PREFERRED STOCK").

C. Prior to the Effective Date of this Agreement, as the holder of the Class A
Preferred Shares, Investor had elected three representatives to the Board of the
Company (the "INVESTOR DIRECTORS").

D. Also on April 4,1995, the Company and Eagle River, Inc., a Washington
corporation ("EAGLE RIVER") entered into a Management Support Agreement (the
"MANAGEMENT SUPPORT AGREEMENT") and an Incentive Option Agreement (the
"INCENTIVE OPTION").

E. The Company, Investor and Individual desire to terminate certain agreements
and modify their relationships as provided in this Agreement.

F. The Incentive Option is not being modified and, in accordance with its terms,
will remain exercisable until April 4, 2005.

                                    AGREEMENT

                          1. TERMINATION OF AGREEMENTS

1.1 TERMINATION OF SPA. On the Effective Date, the SPA will terminate. From and
after the Effective Date, the SPA will be void and have no further force or
effect.

1.2 TERMINATION OF MANAGEMENT SUPPORT AGREEMENT. On the Effective Date and from
and after effective the Effective Date, the Company and Eagle River will
terminate the Management Support Agreement.

                         2. CONDITIONS TO EFFECTIVENESS

2.1 EFFECTIVE DATE. The Effective Date of this Agreement shall be the date when
all of the following actions have been taken (the "EFFECTIVE DATE"):


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a.   Investor shall have caused each of the Investor Directors to submit his
     resignation as a director to the Company, which shall provide that such
     resignations shall be effective upon acceptance by action of a majority of
     the members of the Company's Board (excluding the Investor Directors).

b.   The Operations Committee shall have acted by the vote of a majority of its
     Members at a meeting duly called, convened and held, or by unanimous action
     of the Operations Committee, to terminate the existence of the Operations
     Committee, and such action shall have been approved and ratified by the
     Company's Board.

c.   Investor as the holder of the all the issued and outstanding shares of
     Class A Preferred Stock shall have delivered written notice to the Company
     that the holder elects to convert all the outstanding shares of Class A
     Preferred Stock into shares of Class A Common Stock of the Company ("CLASS
     A COMMON STOCK").

d.   Investor as the holder of the issued and outstanding shares of Class B
     Preferred Stock shall have surrendered certificates together with
     instruments of transfer duly executed for all the outstanding Class B
     Preferred Stock in exchange for 82 shares of Class A Common Stock.

2.2 POST-EFFECTIVE DATE COVENANT. The Company, Investor and Individual will each
use its or his respective best efforts to cause each of the actions contemplated
by this Section 2.2 to occur as promptly as practicable after the Effective
Date.

a.   The Directors of the Company shall elect J. Timothy Bryan to serve the
     remainder of the term for the vacancy created by his resignation until the
     annual stockholders meeting of the Company in 2003.

b.   Conditional upon receiving a Required Letter, the Directors of the Company
     shall elect Individual to serve the remainder of the term for the vacancy
     created by his resignation until the annual stockholders meeting of the
     Company in 2004.

c.   Conditional upon receiving a Required Letter, the Directors of the Company
     shall elect Dennis M. Weibling to serve the remainder of the term for the
     vacancy created by his resignation until the annual stockholders meeting of
     the Company in 2005.

d.   Contemporaneously with the actions contemplated in Section 2.2 a., b. and
     c. the Directors of the Company shall approve and the Company shall execute
     indemnification agreements with Individual and Messrs. Bryan and Weibling
     granting to them the same indemnification granted to other non-management
     directors of the Company.

                              3. SOLE WIRELESS PLAY

3.1 EXCLUSIVE WIRELESS PARTICIPATION. From and after the Effective Date, neither
Investor nor any Controlled Affiliate shall: (i)except as contemplated by
Section 3.2, directly or


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indirectly acquire or seek to acquire any license granted by the FCC for two-way
terrestrial-based mobile wireless communications systems, (ii)except for an
investment constituting not more than 3% of the outstanding common stock of ATT
Corporation owned by Individual and for individual investments of not more than
$100,000, own any direct or indirect equity interest in a Person that engages or
proposes to engage in two-way terrestrial-based mobile wireless communications
systems in the region that includes any part of North America or South America,
(iii)serve as an officer, director, employee, manager or consultant of or to a
Person that engages or proposes to engage in two-way terrestrial-based mobile
wireless communications systems in the region that includes any part of North
America or South America unless in each such instance the opportunity to acquire
the FCC license, own the equity interest or serve in that capacity (each a
"WIRELESS OPPORTUNITY") was first offered to the Company pursuant to Section3.2.
Ownership by Investor or any Controlled Affiliate of securities of Western
Wireless, Inc. constituting less than three percent (3%) of its outstanding
capital stock and the purchase of additional securities therein for aggregate
consideration of not more than $1,000,000 in the aggregate shall not be a
violation of this Section3.1 or Section3.2. The terms of this Section3.1 shall
continue to apply to Investor and all Controlled Affiliates until February 13,
2004. As used in this Agreement, "MOBILE" systems include all vehicular and
other portable (hand held or otherwise) systems.

3.2 FIRST RIGHT TO WIRELESS OPPORTUNITY. If Investor or any of the other
Controlled Affiliates becomes aware of a Wireless Opportunity, that Person shall
give notice to the Company under Section6.2 of the Wireless Opportunity and, to
the extent known, of the circumstances surrounding the Wireless Opportunity. As
promptly as practicable following such notification, the President shall report
to the Board his recommendation concerning whether the Company should pursue the
Wireless Opportunity. Following the report of the President, not more than
30days after such notification, a majority of Disinterested Directors will elect
whether or not to pursue such Wireless Opportunity. If the Company elects not to
pursue such Wireless Opportunity, Investor, Individual and their respective
Affiliates shall be free to pursue that Wireless Opportunity for its, his or
their own account on terms no more favorable to the other party than those
offered to the Company. The Company, Investor and Individual shall use their
respective good faith best efforts to create and put in place appropriate
mechanisms to ensure reasonable and effective protection for confidential
information of Investor or Individual disclosed pursuant to this Section3.2.

3.3 CONFIDENTIAL INFORMATION AND ACTUAL OR POTENTIAL CONFLICTS. If Investor,
Individual or any of the other Controlled Affiliates pursued a "wireless
opportunity" under Section8.3(b) of the SPA or pursues a Wireless Opportunity
for its or their own account as permitted by Section3.2, the Company, Investor
and Individual shall use their respective good faith best efforts to create and
put in place appropriate mechanisms to ensure reasonable and effective
protection for confidential information of the Company and otherwise to minimize
the prospect of any apparent or actual conflict of interest between pursuit of
such Wireless Opportunity and the conduct of the Company's wireless
communications businesses. The obligations of Investor and Individual under the
preceding sentence shall continue for so long as it or he, or any of their
respective Affiliates, equity holders, officers, directors, managers, employees
or nominees are or is proposed to be a Director or an officer of the Company,
and shall be in addition to, and not a limitation on or in lieu of, any other
obligations imposed on such Persons or entities pursuant to applicable Law or
fiduciary obligations.


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                        4. REPRESENTATIONS AND WARRANTIES

4.1 By COMPANY. The Company hereby represents and warrants to Investor and
Individual that:

a.   The Company is a corporation duly organized, validly existing and in good
     standing under the laws of the state of Delaware and has all requisite
     corporate or other power and authority to carry on its business as now
     conducted, and to enter into and to perform this agreement.

b.   The Company has taken all necessary corporate action to authorize the
     execution and delivery and, when the actions necessary to the Effective
     Date have occurred, the performance of this Agreement. This Agreement has
     been duly executed and delivered by the Company and constitutes a valid and
     binding agreement of the Company enforceable against the Company in
     accordance with its terms, except as may be limited by applicable
     bankruptcy, insolvency, reorganization, moratorium and other similar laws
     of general application which may affect the enforcement of creditors'
     rights generally and by general equitable principles.

c.   To the best of the Company's knowledge, it has complied with all of its
     obligations and performed all of its duties under the SPA to and
     including the Effective Date, and it is not aware of any existing breach by
     Individual or Investor of their respective obligations or duties under the
     SPA.

4.2 BY INVESTOR. Investor hereby represents and warrants to the Company that:

a.   The Investor is a limited liability company duly organized, validly
     existing and in good standing under the laws of the state of Washington
     and has all requisite limited liability company or other power and
     authority to carry on its business as now conducted, and to enter into and
     to perform this agreement.

b.   The Investor has taken all necessary action to authorize the execution and
     delivery and the performance of this Agreement. This Agreement has been
     duly executed and delivered by the Investor and constitutes a valid and
     binding agreement of the Investor enforceable against the Investor in
     accordance with its terms, except as may be limited by applicable
     bankruptcy, insolvency, reorganization, moratorium and other similar laws
     of general application which may affect the enforcement of creditors'
     rights generally and by general equitable principles.

c.   To the best of the Investor's knowledge, it has complied with all of its
     obligations and performed all of its duties under the SPA to and
     including the Effective Date, and it is not aware of any existing breach by
     the Company of its obligations and duties under the SPA.

4.3 BY INDIVIDUAL. Individual represents and warrants to the Company that:

a.   Individual is a resident of the State of Washington and is authorized to
     execute, deliver and perform this Agreement without the need to obtain
     the consent or


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     approval of any third party (other than any such consent or approval
     already obtained). This Agreement has been duly executed and delivered by
     Individual and constitutes a valid and binding agreement of Individual
     enforceable against Individual in accordance with its terms, except as may
     be limited by applicable bankruptcy, insolvency, reorganization, moratorium
     and other similar laws of general application which may affect the
     enforcement of creditors' rights generally and by general equitable
     principles.

b.   Individual Controls Eagle River and Eagle River has taken all necessary
     corporate action to authorize the termination of the Management Support
     Agreement.

c.   To the best of the Individual's knowledge, he and his Controlled Affiliates
     have complied with all of his and their respective obligations and
     performed all of its duties under the SPA to and including the Effective
     Date, and he is not aware of any existing breach by the Company of its
     obligations and duties under the SPA.

                                 5. DEFINITIONS

5.1 CERTAIN DEFINITIONS

"AFFILIATE" means, as to any Person, another Person that directly or indirectly
through one or more intermediaries, Controls, or is Controlled by, or is under
common Control with, such Person. For the purposes of this definition, "CONTROL"
when used with respect to any Person, means the possession, directly or
indirectly, of the power to direct or cause the direction of the management and
policies of such Person, whether through the ownership of voting securities, by
contract or otherwise; the terms "CONTROLLING" and "CONTROLLED" have meanings
correlative to the foregoing; provided, that the term "CONTROLLED AFFILIATE" as
used herein includes Individual and any Affiliate of Individual that is, at the
relevant time, Controlled by Individual; and further provided, that the Company
and Investor shall not be deemed to be direct or indirect Affiliates of each
other.

"BOARD" means the Board of the Company.

"DIRECTORS" means any and all of the duly elected members of the Board.

"DISINTERESTED DIRECTOR" means with respect to any contract or transaction
between the Company and any other Person that is the subject of any vote by the
Board, members of the Board who would not be a party to, or who would not have a
financial interest in, such contract or transaction (an "INTERESTED PARTY") and
are not at the time of such vote and are not expected to become following such
vote either Directors of the Company who are nominees of, or who are Affiliates
of, such an Interested Party or officers, directors, or employees of, and do not
have (and are not expected to receive) a financial interest in, such an
Interested Party. For purposes of this definition, no person would be deemed not
to be a Disinterested Director solely because such person is the beneficial
owner of any voting securities of the Company, but no Director that is an
Affiliate of Investor or of any of its Controlled Affiliates shall be a
Disinterested Director


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for purposes of considering any Wireless Opportunity or any transaction with
Investor or any of its Affiliates.

"FCC" means the Federal Communications Commission.

"GOVERNMENTAL AUTHORITY" means any governmental or political subdivision or
department thereof, any governmental or regulatory body, commission, board,
bureau, agency or instrumentality, or any court or arbitrator or alternative
dispute resolution body, in each case whether domestic or foreign, federal,
state or local.

"LAW" means any domestic or foreign, federal, state or local law, statute,
ordinance, rule or regulation.

"PERSON" means an individual, partnership, corporation, limited liability
company, business trust, joint stock company, trust, unincorporated association,
joint venture, Governmental Authority or other, entity of whatever nature or a
group, including without limitation any pension, profit sharing or other benefit
plan or trust.

"REQUIRED LETTER" means an undated resignation letter from the individual
being elected which resignation can be accepted by the Board if the stockholders
of the Company do not ratify his election at the next annual meeting of the
Company's stockholders.

5.2 OTHER DEFINITIONAL PROVISIONS.

a.   All terms defined in this Agreement have the defined meanings when used in
     any certificate, report or other documents made or delivered pursuant
     hereto or thereto, unless the context otherwise requires.

b.   Terms defined in the singular have a comparable meaning when used in the
     plural, and vice versa.

c.   As used herein, the neuter gender also denotes the masculine and feminine,
     and the masculine gender also denotes the neuter and feminine, where the
     context so permits.

d.   The words "INCLUDE," "INCLUDING" and "OR" mean without limitation by
     reason of enumeration.

                                   6. GENERAL

6.1 PUBLIC ANNOUNCEMENTS. Except as required by Law, the exercise of fiduciary
duty or the policies or rules of any stock exchange (or the NASDAQ-NMS) on which
the Company's securities are listed, the form and content of all press releases
or other public communications of any sort relating to the subject matter of
this Agreement, and the method of their release, or publication thereof by any
of the parties hereto or their respective Affiliates, shall be subject to the
prior approval of Investor and the Company, which approval shall not be
unreasonably withheld or delayed.


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6.2 NOTICES. All notices, demands, requests, certificates or other
communications under this Agreement shall be in writing and shall be deemed to
have been duly given when (i)hand delivered, (ii)sent by facsimile transmission
or by tested or otherwise authenticated telex or cable, (iii)one day after sent
by commercial courier guaranteeing next business day delivery or (iv)five days
after posting in the United States mail having been sent by registered or
certified mail return receipt requested, addressed as follows:

(i)  if to Company:

     Nextel Communications, Inc.
     2001 Edmund Halley Drive
     Reston, VA 20191
     Attention: Timothy M. Donahue, President
     Facsimile: (703)433-4352

     with a copy to:

     Nextel Communications, Inc.
     2001 Edmund Halley Drive
     Reston, VA 20191
     Attention: Leonard J. Kennedy, General Counsel
     Facsimile: (703)433-4846

(ii) if to Individual or Investor:

     Digital Radio, L.L.C.
     2320 Carillon Point
     Kirkland, WA 94104-2675
     Attention: Dennis Weibling
     Facsimile: (206)828-8060

     with a copy to:

     Digital Radio, L.L.C.
     2320 Carillon Point
     Kirkland, WA 94104-2675
     Attention: J. Timothy Bryan
     Facsimile: (206)828-8060

Any communication delivered after business hours or on a Saturday, Sunday or
legal holiday at the place designated in such delivery shall be deemed for
purposes of computing any time period hereunder to have been delivered on the
next business day.

6.3 EXPENSES. Each party shall bear its own expenses, including the fees and
expenses of any attorneys, accountants, investment bankers, brokers, finders or
other intermediaries or other Persons engaged by Investor or the Company,
incurred in connection with this Agreement or the other agreements contemplated
hereby.


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6.4 BENEFITS; ASSIGNMENT. The provisions of this Agreement shall be binding
upon, and inure to the benefit of, Investor and the Company and their respective
successors and permitted assigns. Nothing in this Agreement, express or implied,
is intended to confer upon any Person other than Investor and the Company and
their respective successors and permitted assigns any rights, remedies or
obligations under or by reason of this Agreement. None of the rights or
obligations of the Company hereunder may be assigned without the consent of
Investor. None of the rights of the Investor or Individual hereunder may be
assigned without the consent of the Company.

6.5 ENTIRE AGREEMENT; AMENDMENT AND WAIVER. This Agreement (which includes the
Exhibits and Annexes hereto) and the other documents to be executed pursuant to
Section 1.2 and the Required Letters to which either Investor or any of its
Controlled Affiliates or the Company is a party constitute the entire agreement
between Investor and its Controlled Affiliates, on the one hand, and the
Company, on the other hand, with respect to the subject matter hereof and
thereof and supersede all prior agreements and understandings, both written and
oral, between Investor and its Controlled Affiliates, on the one hand, and the
Company, on the other hand, with respect to the subject matter hereof and
thereof. This Agreement may not be amended, supplemented or otherwise modified
except by an instrument in writing signed by each of the parties hereto. No
waiver by either party hereto of any of the provisions hereof shall be effective
unless explicitly set forth in writing and executed by such party. Any waiver by
a party of a breach of this Agreement shall not operate or be construed as a
waiver of any subsequent breach.

6.6 HEADINGS. The headings in this Agreement are for convenience only and shall
not affect the construction hereof.

6.7 GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF DELAWARE WITHOUT GIVING EFFECT
TO ANY CONFLICTS OF LAW PRINCIPLES OF SUCH STATE.

6.8 REMEDIES.

a.   Each of Investor and its Controlled Affiliates, on the one hand, and the
     Company, on the other hand, acknowledges that the other party (or parties)
     would not have an adequate remedy at Law for money damages in the event
     that any of the covenants or agreements of such party in this Agreement was
     not performed in accordance with its terms, and it is therefore agreed that
     each of Investor and its Controlled Affiliates, on the one hand, and the
     Company, on the other hand, in addition to and without limiting any other
     remedy or right such party may have, shall have the right to an injunction
     or other equitable relief in any court of competent jurisdiction, enjoining
     any such breach and enforcing specifically the terms and provisions hereof,
     and each of Investor and its Controlled Affiliates, on the one hand, and
     the Company, on the other hand, hereby waive any and all defenses such
     party may have on the ground of lack of jurisdiction or competence of the
     court to grant such an injunction or other equitable relief.


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b.   All rights, powers and remedies provided under this Agreement or otherwise
     available in respect hereof at Law or in equity shall be cumulative and not
     alternative, and the exercise or beginning of the exercise of any thereof
     by any party shall not preclude the simultaneous or later exercise of any
     other such right, power or remedy by such party.

6.9 SEVERABILITY. In the event that any provision of this Agreement is deemed
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.

6.10 COUNTERPARTS. This Agreement may be executed in one or more counterparts,
each of which shall be deemed an original, and it shall not be necessary in
making proof of this Agreement to produce or account for more than one such
counterpart.

6.11 COMMUNICATIONS ACT. Nothing in this Agreement is intended or shall be
construed to diminish or affect the control of the Company or any of its
subsidiaries over any FCC licenses held by the Company or such subsidiary in any
manner prohibited by the Communications Act of 1934, as amended, or the rules
and regulations issued by the FCC.

6.12 FURTHER ASSURANCES. Each of Investor and Individual (and his Controlled
Affiliates, if appropriate) will cooperate with the Company in effecting the
amendment or termination of other documents (such as, without limitation, the
Company's Certificate of Incorporation and By-Laws) that may, in the Company's
reasonable judgment, be necessary or desirable to reflect, confirm or conform to
the matters and actions contemplated in this Agreement.

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly
executed and delivered as of the day and year first above written.

                                        NEXTEL COMMUNICATIONS, INC


                                        By: /s/ Leonard J. Kennedy
                                            ------------------------------------
                                        Name: Leonard J. Kennedy
                                        Title: Senior Vice President and
                                               General Counsel


                                        DIGITAL RADIO, L.L.C


                                        By: /s/ Craig O. McCaw
                                            ------------------------------------
                                        Name: Craig O. McCaw
                                        Title: Chairman and Chief Executive
                                               Officer


                                        /s/ Craig O. McCaw
                                        ----------------------------------------
                                        CRAIG O. MCCAW,
                                        for his sole and separate estate


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