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EXHIBIT 4.3

                           NEXTEL COMMUNICATIONS, INC.

                                       and

                              THE BANK OF NEW YORK,
                                   AS TRUSTEE




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                          FOURTH SUPPLEMENTAL INDENTURE

                           Dated as of March 24, 1998


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                                       To

                    The Indenture Dated as of August 15, 1993
                     Between NEXTEL Communications, Inc. and
                  The Bank of New York, as Trustee, Relating to
     $525,855,000 Aggregate Principal Amount at Maturity (originally issued)
                  of Senior Redeemable Discount Notes due 2003


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                             SUPPLEMENTAL INDENTURE

     THIS FOURTH SUPPLEMENTAL INDENTURE (the "SUPPLEMENTAL INDENTURE") is made
as of the 24th day of March, 1998, between NEXTEL COMMUNICATIONS, INC., a
corporation duly organized and existing under the laws of the State of Delaware
(the "COMPANY"), and THE BANK OF NEW YORK, a New York banking corporation, as
Trustee (the "TRUSTEE").

                             RECITALS OF THE COMPANY

     WHEREAS, the Company and the Trustee heretofore executed and delivered an
Indenture, dated as of August 15, 1993, as heretofore amended (the "INDENTURE");
and

     WHEREAS, pursuant to the Indenture, the Company issued and the Trustee
authenticated and delivered $525,855,000 aggregate principal amount at maturity
of the Company's Senior Redeemable Discount Notes due 2003 (the "SECURITIES");
and

     WHEREAS, the Company desires to make certain modifications to the
provisions of the Indenture; and

     WHEREAS, Section 902 of the Indenture provides that with the consent of not
less than a majority in principal amount at Stated Maturity of the Securities at
the time Outstanding (the "REQUISITE AMENDMENT CONSENTS"), the Company, when
authorized by a resolution of its Board of Directors, and the Trustee may enter
into an indenture or indentures supplemental to the Indenture for the purpose of
adding provisions to, or changing or eliminating certain provisions of, the
Indenture, subject to certain exceptions specified in Section 902 of the
Indenture; and

     WHEREAS, the Company has obtained the Requisite Amendment Consents to amend
the Indenture in certain respects (the "PROPOSED AMENDMENTS"); and

     WHEREAS, this Supplemental Indenture has been duly authorized by all
necessary corporate action on the part of the Company; and

     WHEREAS, the Company has delivered, or caused to be delivered, to the
Trustee, an Opinion of Counsel stating that this Supplemental Indenture complies
with the requirements of the Indenture;

     NOW, THEREFORE, the Company hereby covenants and agrees with the Trustee
for the equal and proportionate benefit of all Holders of the Securities, as
follows:

                                    ARTICLE 1
                  AMENDMENTS TO CERTAIN PROVISIONS OF INDENTURE

     SECTION 1.01. AMENDMENT OF CERTAIN SECTIONS OF THE INDENTURE. Subject to
Section 2.01 hereof, the Indenture is hereby amended in the following respects:

          (a) Sections 1008, 1010, 1012, 1013, 1015, and 1017 of the Indenture
     and any references to any of such Sections in any of the provisions of the
     Indenture are hereby deleted from the Indenture.

          (b) The following text appearing in Section 801 of the Indenture is
     hereby deleted therefrom:

     ", and (iii) the Company or the Surviving Entity, as the case may be, after
     giving effect to such transaction or series of transactions on a pro forma
     basis (including any Debt Incurred or anticipated to be Incurred in
     connection with or in respect of such transaction or series of
     transactions), could Incur $1.00 of additional Debt (other than Permitted
     Debt) pursuant to Section 1008 and the Consolidated Net Worth of the
     Company or the Surviving Entity, as the case may be, shall be equal to or
     greater than that of the Company immediately prior to such transaction or
     series of transactions"

          (c) The following text appearing in Section 801 of the Indenture is
     hereby deleted therefrom:


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     "Each such Officers' Certificate shall set forth the manner of
     determination of the Consolidated Net Worth and the ability to Incur Debt
     in accordance with Clause (iii) of Section 801."

          (d) Any references to clause (iii) of Section 801 of the Indenture in
     any of the provisions of the Indenture are hereby deleted from the
     Indenture.

          (e) Section 1011 of the Indenture is hereby amended to read in its
     entirety as follows:

          "Section 1011. Restricted Subsidiaries.

          The Board of Directors may, at any time, designate any existing
     Unrestricted Subsidiary or any Person that is about to become a Subsidiary
     of the Company as a Restricted Subsidiary. The Board of Directors may, at
     any time, designate any existing Restricted Subsidiary or any Person that
     is about to become a Subsidiary of the Company as an Unrestricted
     Subsidiary. Subsidiaries of the Company that are not designated by the
     Board of Directors as Restricted or Unrestricted Subsidiaries will be
     deemed to be Restricted Subsidiaries. Unless otherwise designated by the
     Board of Directors pursuant to this Section 1011, all Subsidiaries of a
     Restricted Subsidiary shall be deemed to be Restricted Subsidiaries and all
     Subsidiaries of an Unrestricted Subsidiary shall be deemed to be
     Unrestricted Subsidiaries."

                                    ARTICLE 2
                                SUNDRY PROVISIONS

     SECTION 2.01. EFFECT OF SUPPLEMENTAL INDENTURE. Upon the execution and
delivery of this Supplemental Indenture by the Company and the Trustee, the
Indenture shall be supplemented in accordance herewith, and this Supplemental
Indenture shall form a part of the Indenture for all purposes, and every Holder
of Securities heretofore or hereafter authenticated and delivered under the
Indenture shall be bound thereby; provided, however, that Section 1.01 hereof
will become effective upon the Company's acceptance for payment of validly
tendered Securities on the applicable Acceptance Date, as such term is defined
in the Offer to Purchase and Consent Solicitation Statement, dated March 3,
1998, as amended, modified or supplemented, that was provided to Holders of
Securities in connection with the Company's solicitation of consents by such
Holders to the Proposed Amendments.

     SECTION 2.02. INDENTURE REMAINS IN FULL FORCE AND EFFECT. Except as
supplemented hereby, all provisions in the Indenture shall remain in full force
and effect.

     SECTION 2.03. INDENTURE AND SUPPLEMENTAL INDENTURE CONSTRUED TOGETHER. This
Supplemental Indenture is an indenture supplemental to and in implementation of
the Indenture, and the Indenture and this Supplemental Indenture shall
henceforth be read and construed together.

     SECTION 2.04. CONFIRMATION AND PRESERVATION OF INDENTURE. The Indenture as
supplemented by this Supplemental Indenture is in all respects confirmed and
preserved.

     SECTION 2.05. CONFLICT WITH TRUST INDENTURE ACT. If any provision of this
Supplemental Indenture limits, qualifies or conflicts with any provision of the
Trust Indenture Act that is required under such Act to be part of and govern any
provision of this Supplemental Indenture, the provision of such Act shall
control. If any provision of this Supplemental Indenture modifies or excludes
any provision of the Trust Indenture Act that may be so modified or excluded,
the provision of such Act shall be deemed to apply to the Indenture as so
modified or to be excluded by this Supplemental Indenture, as the case may be.

     SECTION 2.06. SEPARABILITY CLAUSE. In case any provision in this
Supplemental Indenture shall be invalid, illegal or unenforceable, the validity,
legality and enforceability of the remaining provisions shall not in any way be
affected or impaired thereby.

     SECTION 2.07. TERMS DEFINED IN THE INDENTURE. All capitalized terms not
otherwise defined herein shall have the meanings ascribed to them in the
Indenture.


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     SECTION 2.08. EFFECT OF HEADINGS. The Article and Section headings herein
are for convenience only and shall not affect the construction hereof.

     SECTION 2.09. BENEFITS OF SUPPLEMENTAL INDENTURE, ETC. Nothing in this
Supplemental Indenture, the Indenture or the Securities, express or implied,
shall give to any Person, other than the parties hereto and thereto and their
successors hereunder and thereunder and the Holders of Securities, any benefit
of any legal or equitable right, remedy or claim under the Indenture, this
Supplemental Indenture or the Securities.

     SECTION 2.10. SUCCESSORS AND ASSIGNS. All covenants and agreements in this
Supplemental Indenture by the Company shall bind its successors and assigns,
whether so expressed or not.

     SECTION 2.11. TRUSTEE NOT RESPONSIBLE FOR RECITALS. The recitals contained
herein shall be taken as the statements of the Company, and the Trustee assumes
no responsibility for their correctness.

     SECTION 2.12. CERTAIN DUTIES AND RESPONSIBILITIES OF THE TRUSTEE. In
entering into this Supplemental Indenture, the Trustee shall be entitled to the
benefit of every provision of the Indenture relating to the conduct or affecting
the liability of or affording protection to the Trustee, whether or not
elsewhere herein so provided.

     SECTION 2.13. GOVERNING LAW. This Supplemental Indenture shall be governed
by and construed in accordance with the laws of the State of New York, without
regard to the conflicts of law principles thereof.

     SECTION 2.14. COUNTERPARTS. This Supplemental Indenture may be executed in
counterparts, each of which, when so executed, shall be deemed to be an
original, but all such counterparts shall together constitute but one and the
same instrument.

     IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed and attested, all as of the date and year first
above written.

                                            NEXTEL COMMUNICATIONS, INC.

                                            BY:     /s/ STEVEN SHINDLER
                                                    ----------------------------

                                            TITLE:  VICE PRESIDENT
                                                    ----------------------------
ATTEST:

/s/ THOMAS J. SIDMAN
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TITLE: VICE PRESIDENT
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                                            THE BANK OF NEW YORK,
                                            AS TRUSTEE

                                            BY:     /s/ MARY BETH A. LEWICKI
                                                    ----------------------------

                                            TITLE:  ASSISTANT VICE PRESIDENT
                                                    ----------------------------

ATTEST:

/s/ M.L. RINKIN
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TITLE: VICE PRESIDENT
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