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                                                                     EXHIBIT 4.3

                          REGISTRATION RIGHTS AGREEMENT

                              DATED AUGUST 12, 2005

                                      AMONG

                            SIERRA PACIFIC RESOURCES

                                       AND

                      MERRILL LYNCH, PIERCE, FENNER & SMITH
                                  INCORPORATED,

                            AS REPRESENTATIVE OF THE

                               INITIAL PURCHASERS

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                          REGISTRATION RIGHTS AGREEMENT

            This Registration Rights Agreement (the "Agreement") is made and
entered into this 12th day of August, 2005, by and between Sierra Pacific
Resources, a Nevada corporation (the "Company"), and Merrill Lynch, Pierce,
Fenner & Smith Incorporated as representative of the Initial Purchasers (the
"Initial Purchasers"), as contemplated by the Purchase Agreement, dated August
10, 2005 (the "Purchase Agreement"), by and between the Company and the Initial
Purchasers, which provides for the sale by the Company to the Initial Purchasers
of an aggregate of $225,000,000 in principal amount of the Company's [ ]% Senior
Notes due 20[ ] (the "Securities"). In order to induce the Initial Purchasers to
enter into the Purchase Agreement, the Company has agreed to provide the
registration rights set forth in this Agreement. The execution of this Agreement
is a condition to the closing under the Purchase Agreement.

            The Company agrees with the Representative, for the benefit of the
Initial Purchasers and for the benefit of the beneficial owners (including the
Initial Purchasers) from time to time of the Registrable Securities (as
hereinafter defined), as follows:

            1. Definitions.

            As used in this Agreement, the following terms shall have the
following meanings:

            "1933 Act" means the Securities Act of 1933, as amended from time to
time.

            "1934 Act" means the Securities Exchange Act of l934, as amended
from time to time.

            "Closing Date" means the Closing Time as defined in the Purchase
Agreement.

            "Company" has the meaning set forth in the preamble and shall also
include the Company's successors.

            "Depositary" means The Depository Trust Company, or any other
depositary appointed by the Company; provided, however, that such depositary
must have an address in the Borough of Manhattan, in the City of New York.

            "Exchange Offer" means the exchange offer by the Company of Exchange
Securities for Registrable Securities pursuant to Section 2.1 hereof.

            "Exchange Offer Registration" means a registration under the 1933
Act effected pursuant to Section 2.1 hereof.

            "Exchange Offer Registration Statement" means an exchange offer
registration statement on Form S-4 (or, if applicable, on another appropriate
form), and

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all amendments and supplements to such registration statement, including the
Prospectus contained therein, all exhibits thereto and all documents
incorporated by reference therein.

            "Exchange Period" has the meaning set forth in Section 2.1 hereof.

            "Exchange Securities" means the notes issued by the Company under
the Indenture containing terms identical to the Securities in all material
respects (except for references to provisions relating to liquidated damages,
restrictions on transfers and restrictive legends), to be offered to Holders of
Securities in exchange for Registrable Securities pursuant to the Exchange
Offer.

            "Holder" means an Initial Purchaser, for so long as it owns any
Registrable Securities, and any other beneficial owner of Registrable
Securities.

            "Indenture" means the Indenture, dated as of May 1, 2000, between
the Company and the Trustee, as amended and supplemented from time to time in
accordance with the terms thereof.

            "Initial Purchaser" or "Initial Purchasers" has the meaning set
forth in the preamble.

            "Majority Holders" means the Holders of a majority in aggregate
principal amount of Outstanding (as defined in the Indenture) Registrable
Securities; provided, however, that whenever the consent or approval of Holders
of a specified percentage of Registrable Securities is required hereunder,
Registrable Securities held by the Company and other obligors on the Securities
or any Affiliate (as defined in the Indenture) of the Company or of such other
obligor (unless the Company, such obligor or such Affiliate owns all Registrable
Securities then Outstanding) shall be disregarded in determining whether such
consent or approval was given by the Holders of such required percentage.

            "Participating Broker-Dealer" means any of the Initial Purchasers
and any other broker-dealer which makes a market in the Securities and exchanges
Registrable Securities in the Exchange Offer for Exchange Securities.

            "Person" means an individual, partnership (general or limited),
corporation, limited liability company, trust or unincorporated organization, or
a government or agency or political subdivision thereof.

            "Private Exchange" has the meaning set forth in Section 2.1 hereof.

            "Private Exchange Securities" has the meaning set forth in Section
2.1 hereof.

            "Prospectus" means the prospectus included in a Registration
Statement, including, without limitation, a prospectus that discloses
information previously omitted from a prospectus filed as part of an effective
registration statement in reliance upon Rule

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415 under the 1933 Act), as amended or supplemented, including all documents
incorporated by reference therein.

            "Purchase Agreement" has the meaning set forth in the preamble.

            "Registrable Securities" means the Securities and, if issued, the
Private Exchange Securities; provided, however, that Securities and, if issued,
the Private Exchange Securities, shall cease to be Registrable Securities when
(i) (except in the case of Securities purchased from the Company and continued
to be held by the Initial Purchasers) the Exchange Offer is consummated, (ii) a
Registration Statement with respect to such Securities shall have been declared
effective under the 1933 Act and such Securities shall have been disposed of
pursuant to such Registration Statement, (iii) such Securities have been sold to
the public pursuant to Rule 144 under the 1933 Act, (iv) the applicable holding
period under rule 144(k) under the 1933 Act shall have expired or (v) such
Securities shall have ceased to be outstanding.

            "Registration Expenses" means any and all expenses incident to
performance of or compliance by the Company with this Agreement, including,
without limitation: (i) all SEC, stock exchange or National Association of
Securities Dealers, Inc. (the "NASD") registration and filing fees, including,
if applicable, the fees and expenses of any "qualified independent underwriter"
(and its counsel) that is required to be retained by any holder of Registrable
Securities in accordance with the rules and regulations of the NASD, (ii) all
fees and expenses incurred in connection with compliance with state securities
or blue sky laws (including reasonable fees and disbursements of counsel for any
underwriters or Holders in connection with blue sky qualification of any of the
Exchange Securities or Registrable Securities), (iii) all printing and other
expenses in preparing, and distributing any Registration Statement, any
Prospectus, any amendments or supplements thereto, any underwriting agreements,
securities sales agreements and other documents relating to the performance of
and compliance with this Agreement, (iv) all rating agency fees, (v) all fees
and disbursements of counsel for the Company and of the independent public
accountants of the Company, (vi) the fees and expenses of the Trustee and its
counsel (vii) the reasonable fees and expenses, if any, of the Initial
Purchasers in connection with the Exchange Offer, including the reasonable fees
and expenses, if any, of not more than one counsel to the Initial Purchasers in
connection therewith, which shall be Dewey Ballantine LLP, (viii) the reasonable
fees and disbursements of not more than one counsel representing the Holders of
Registrable Securities which shall be Dewey Ballantine LLP, unless another firm
shall be chosen by the Majority Holders and identified to the Company and (ix)
any fees and disbursements of the underwriters customarily required to be paid
by issuers or sellers of securities, but excluding underwriting discounts and
commissions and transfer taxes, if any, relating to the sale or disposition of
Registrable Securities by a Holder.

            "Registration Statement" means any registration statement of the
Company which covers any of the Exchange Securities or Registrable Securities
pursuant to the provisions of this Agreement, and all amendments and supplements
to any such Registration Statement, including post-effective amendments, in each
case including the

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Prospectus contained therein, all exhibits thereto and all documents
incorporated by reference therein.

            "SEC" means the Securities and Exchange Commission or any successor
agency or government body performing the functions currently performed by the
United States Securities and Exchange Commission.

            "Securities" has the meaning set forth in the preamble.

            "Shelf Registration" means a registration effected pursuant to
Section 2.2 hereof.

            "Shelf Registration Statement" means a "shelf" registration
statement of the Company pursuant to the provisions of Section 2.2 of this
Agreement which covers all of the Registrable Securities or all of the Private
Exchange Securities on an appropriate form under Rule 415 under the 1933 Act, or
any similar rule that may be adopted by the SEC, and all amendments and
supplements to such registration statement, including post-effective amendments,
in each case including the Prospectus contained therein, all exhibits thereto
and all material incorporated by reference therein.

            "Trustee" means the trustee with respect to the Securities under the
Indenture.

            2.    Registration Under the 1933 Act.

            2.1   Exchange Offer. The Company shall, for the benefit of the
Holders, at the Company's cost,

                        (A) prepare and, as soon as reasonably practicable but
      not later than the 180th day after the Closing Date, file with the SEC an
      Exchange Offer Registration Statement on an appropriate form under the
      1933 Act with respect to a proposed Exchange Offer and the issuance and
      delivery to the Holders, in exchange for the Registrable Securities (other
      than Private Exchange Securities), of a like principal amount of Exchange
      Securities,

                        (B) use all commercially reasonable efforts to cause the
      Exchange Offer Registration Statement to be declared effective under the
      1933 Act on or prior to the 270th day after the Closing Date,

                        (C) to commence the Exchange Offer as promptly as
      reasonably practicable after the effective date of the Exchange Offer
      Registration Statement,

                        (D) use all commercially reasonable efforts to keep the
      Exchange Offer Registration Statement effective until the closing of the
      Exchange Offer, and

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                        (E) use all commercially reasonable efforts to cause the
      Exchange Offer to be consummated not later than the 40th day after such
      effective date. It is the objective of the Exchange Offer to enable each
      Holder eligible and electing to exchange Registrable Securities for
      Exchange Securities (assuming that such Holder (a) is not an affiliate of
      the Company within the meaning of Rule 405 under the 1933 Act, (b) is not
      a broker-dealer tendering Registrable Securities acquired directly from
      the Company for its own account, (c) acquired the Exchange Securities in
      the ordinary course of such Holder's business and (d) has no arrangements
      or understandings with any Person to participate in the Exchange Offer for
      the purpose of distributing the Exchange Securities) to transfer such
      Exchange Securities from and after their receipt without any limitations
      or restrictions under the 1933 Act or under state securities or blue sky
      laws.

            In connection with the Exchange Offer, the Company shall:

                  (a)   mail as promptly as reasonably practicable to each
      Holder a copy of the Prospectus forming part of the Exchange Offer
      Registration Statement, together with an appropriate letter of transmittal
      and related documents;

                  (b)   keep the Exchange Offer open for acceptance for a period
      of not less than 30 calendar days after the date notice thereof is mailed
      to the Holders (or longer if required by applicable law) (such period
      referred to herein as the "Exchange Period");

                  (c)   utilize the services of the Depositary for the Exchange
      Offer;

                  (d)   permit Holders to withdraw tendered Registrable
      Securities at any time prior to 5:00 p.m. (Eastern Time), on the last
      business day of the Exchange Period, by sending to the institution
      specified in the notice, a telegram, telex, facsimile transmission or
      letter setting forth the name of such Holder, the principal amount of
      Registrable Securities delivered for exchange, and a statement that such
      Holder is withdrawing such Holder's election to have such Securities
      exchanged;

                  (e)   notify each Holder that any Registrable Security not
      tendered will remain Outstanding and continue to accrue interest, but will
      not retain any rights under this Agreement (except in the case of the
      Initial Purchasers and Participating Broker-Dealers, as provided herein);
      and

                  (f)   otherwise comply in all respects with all applicable
      laws relating to the Exchange Offer.

            If, prior to consummation of the Exchange Offer, the Initial
Purchasers hold any Securities acquired by them and having the status of an
unsold allotment in the initial distribution, the Company upon the request of
any Initial Purchaser shall,

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simultaneously with the delivery of the Exchange Securities in the Exchange
Offer, issue and deliver to such Initial Purchaser in exchange (the "Private
Exchange") for the Securities held by such Initial Purchaser, a like principal
amount of debt securities (the "Private Exchange Securities") of the Company
issued under the Indenture and identical (except that such securities shall bear
appropriate transfer restrictions) to the Exchange Securities.

            The Company shall use all commercially reasonable efforts to have
the Private Exchange Securities bear the same CUSIP number as the Exchange
Securities; provided, however, that the Company shall not have any liability
under this Agreement solely as a result of the Private Exchange Securities not
bearing the same CUSIP number as the Exchange Securities.

            As soon as practicable after the consummation of the Exchange Offer
and/or the Private Exchange, as the case may be, the Company shall:

                        (ii) accept for exchange all Registrable Securities duly
            tendered and not validly withdrawn pursuant to the Exchange Offer in
            accordance with the terms of the Exchange Offer Registration
            Statement and the letter of transmittal which shall be an exhibit
            thereto;

                        (iii) accept for exchange all Securities properly
            tendered pursuant to the Private Exchange;

                        (iv) deliver to the Trustee for cancellation all
            Registrable Securities so accepted for exchange; and

                        (v) cause the Trustee promptly to authenticate and
            deliver Exchange Securities or Private Exchange Securities, as the
            case may be, to each Holder of Registrable Securities so accepted
            for exchange in a principal amount equal to the principal amount of
            the Registrable Securities of such Holder so accepted for exchange.

            Interest on each Exchange Security and Private Exchange Security
will accrue from the last date on which interest was paid on the Registrable
Securities surrendered in exchange therefor or, if no interest has been paid on
the Registrable Securities, from the date as of which interest on such
Registrable Securities commenced to accrue, all as provided in the Indenture.
The Exchange Offer and the Private Exchange shall not be subject to any
conditions, other than the following:

                        (i) the Exchange Offer or the Private Exchange, or the
            making of any exchange by a Holder, shall not be in violation of
            applicable law or any applicable interpretation of the staff of the
            SEC,

                        (ii) the Registrable Securities to be exchanged shall
            have been duly tendered in accordance with the Exchange Offer and
            the Private Exchange,

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                        (iii) each Holder of Registrable Securities to be
            exchanged in the Exchange Offer shall have represented that all
            Exchange Securities to be received by it shall be acquired in the
            ordinary course of its business and that at the time of the
            consummation of the Exchange Offer it shall have no arrangement or
            understanding with any person to participate in the distribution
            (within the meaning of the 1933 Act) of the Exchange Securities and
            shall have made such other representations as may be reasonably
            necessary under applicable SEC rules, regulations or interpretations
            to render the use of Form S-4 or other appropriate form under the
            1933 Act available, and

                        (iv) no action or proceeding shall have been instituted
            or threatened in any court or by or before any governmental agency
            with respect to the Exchange Offer or the Private Exchange which, in
            the Company's judgment, would reasonably be expected to impair the
            ability of the Company to proceed with the Exchange Offer or the
            Private Exchange. The Company shall inform the Initial Purchasers of
            the names and addresses of the Holders to whom the Exchange Offer is
            made, and the Initial Purchasers shall have the right (but shall
            have no obligation hereunder) to contact such Holders and otherwise
            facilitate the tender of Registrable Securities in the Exchange
            Offer.

            2.2   Shelf Registration. (i) If, because of any changes in law, SEC
rules or regulations or applicable interpretations thereof by the staff of the
SEC, the Company is not permitted to effect the Exchange Offer as contemplated
by Section 2.1 hereof, (ii) if for any other reason the Exchange Offer
Registration Statement is not declared effective on or prior to the 270th day
after the Closing Date or the Exchange Offer is not consummated on or prior to
the 40th day after the effective date of the Exchange Offer Registration
Statement, or (iii) if any Holder is not permitted to participate in the
Exchange Offer or does not receive fully tradeable Exchange Securities pursuant
to the Exchange Offer, then in case of each of clauses (i) through (iii) the
Company shall, at its cost:

                  (a)   File with the SEC, as promptly as reasonably practicable
      but no later than the 30th day after such filing obligation arises, a
      Shelf Registration Statement relating to the offer and sale of the
      Registrable Securities by the Holders from time to time in accordance with
      the methods of distribution elected by the Holders participating in the
      Shelf Registration and set forth in such Shelf Registration Statement, and
      shall use all commercially reasonable efforts to cause the Shelf
      Registration Statement to be declared effective as promptly as reasonably
      practicable but no later than the 90th day after the filing thereof.

                  (b)   Use all commercially reasonable efforts to keep the
      Shelf Registration Statement continuously effective in order to permit the
      Prospectus forming part thereof to be usable by Holders for a period of
      two years from the date the Shelf Registration Statement is declared
      effective by the SEC, or for such shorter period as will terminate when
      all Registrable Securities covered by the

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      Shelf Registration Statement have been sold pursuant to the Shelf
      Registration Statement or cease to be Outstanding or otherwise to be
      Registrable Securities (the "Effectiveness Period"); provided, however,
      that the Effectiveness Period in respect of the Shelf Registration
      Statement shall be extended to the extent required to permit dealers to
      comply with the applicable prospectus delivery requirements of Rule 174
      under the 1933 Act and as otherwise provided herein.

                  (c)   Notwithstanding any other provisions hereof, use its
      best efforts to ensure that (i) any Shelf Registration Statement and any
      amendment thereto and any Prospectus forming part thereof and any
      supplement thereto complies in all material respects with the 1933 Act and
      the rules and regulations thereunder, (ii) any Shelf Registration
      Statement and any amendment thereto does not, when it becomes effective,
      contain an untrue statement of a material fact or omit to state a material
      fact required to be stated therein or necessary to make the statements
      therein not misleading and (iii) any Prospectus forming part of any Shelf
      Registration Statement, and any supplement to such Prospectus (as amended
      or supplemented from time to time), does not include an untrue statement
      of a material fact or omit to state a material fact necessary in order to
      make the statements, in light of the circumstances under which they were
      made, not misleading.

            The Company shall not permit any securities other than Registrable
Securities to be included in the Shelf Registration Statement. The Company
further agrees, if necessary, to supplement or amend the Shelf Registration
Statement, as required by Section 3(b) below, and to furnish to the Holders of
Registrable Securities copies of any such supplement or amendment promptly after
its being used or filed with the SEC.

            2.3 Expenses. The Company shall pay all Registration Expenses in
connection with the registration pursuant to Section 2.1 or 2.2. Each Holder
shall pay all underwriting discounts and commissions and transfer taxes, if any,
relating to the sale or disposition of such Holder's Registrable Securities
pursuant to the Shelf Registration Statement.

            2.4 Effectiveness. (a) The Company will be deemed not to have used
all commercially reasonable efforts to cause the Exchange Offer Registration
Statement or the Shelf Registration Statement, as the case may be, to become, or
to remain, effective during the requisite period if the Company voluntarily
takes any action that would, or omits to take any action the omission of which
would, result in any such Registration Statement not being declared effective or
in the Holders of Registrable Securities covered thereby not being able to
exchange or offer and sell such Registrable Securities during that period as and
to the extent contemplated hereby, unless such action is required or prohibited,
as the case may be, by applicable law.

            (b) An Exchange Offer Registration Statement pursuant to Section 2.1
hereof or a Shelf Registration Statement pursuant to Section 2.2 hereof will not
be deemed to have become effective unless it has been declared effective by the
SEC;

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provided, however, that if, after it has been declared effective, the offering
of Registrable Securities pursuant to an Exchange Offer Registration Statement
or a Shelf Registration Statement is interfered with by any stop order,
injunction or other order or requirement of the SEC or any other governmental
agency or court, such Registration Statement will be deemed not to have become
effective during the period of such interference, until the offering of
Registrable Securities pursuant to such Registration Statement may legally
resume.

            2.5 Liquidated Damages. In the event that either (a) the Exchange
Offer Registration Statement is not filed with the SEC at or prior to the
deadline therefor specified in Section 2.1, (b) the Exchange Offer Registration
Statement has not been declared effective at or prior to the deadline therefor
specified in Section 2.1, (c) the Exchange Offer is not consummated at or prior
to the deadline therefor specified in Section 2.1, (d) the Shelf Registration
Statement is not filed with the SEC at or prior to the deadline therefor
specified in Section 2.2 or (e) the Shelf Registration Statement has not been
declared effective at or prior to the deadline therefor specified in Section 2.2
(each such event referred to in clauses (a) through (e) above, a "Registration
Default"), then the Company shall pay to each Holder of Registrable Securities
affected thereby liquidated damages in an amount equal to $0.05 per $1,000 in
principal amount of Registrable Securities held by such Holder for each week (or
portion thereof) in the first 90-day period immediately following the occurrence
of such Registration Default. The amount of such liquidated damages payable per
week shall increase by $0.05 per $1,000 in principal amount of such Registrable
Securities with respect to each subsequent 90-day period until all Registration
Defaults have been cured, up to a maximum amount of liquidated damages of $0.50
per week per $1,000 in principal amount of Registrable Securities; provided that
the Company shall in no event be required to pay liquidated damages for more
than one Registration Default at any given time. Following the cure of all
Registration Defaults liquidated damages will cease to accrue.

            If the Shelf Registration Statement is unusable by the Holders for
any reason (other than by reason of a prohibition, condition or other
requirement (not relating to information contained therein or omitted therefrom)
not in effect at the date hereof imposed by any statute or governmental
regulation), and the aggregate number of days in any consecutive twelve-month
period for which the Shelf Registration Statement shall not be usable exceeds 30
days in the aggregate, then the Company shall pay to each Holder of Registrable
Securities affected thereby liquidated damages in an amount equal to $0.05 per
$1,000 in principal amount of Registrable Securities held by such Holder for
each week (or portion thereof) in the first 90-day period beginning on the 31st
day on which the Shelf Registration Statement ceases to be usable. The amount of
such liquidated damages shall increase by $0.05 per $1,000 in principal amount
of such Registrable Securities with respect to each subsequent 90-day period in
which the Shelf Registration Statement is not usable, up to a maximum amount of
liquidated damages of $0.50 per week per $1,000 in principal amount of
Registrable Securities. Upon the Shelf Registration Statement once again
becoming usable, liquidated damages will cease to accrue.

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            Liquidated damages shall be computed based on the actual number of
days elapsed in each 90-day period in which a Registration Default is continuing
or in which the Shelf Registration Statement is unusable, as the case may be.

            All accrued liquidated damages shall be paid to the Holders entitled
thereto, in the manner provided in the Indenture for the payment of interest, on
each interest payment date, as more fully set forth in the Indenture and the
Securities. Notwithstanding the fact that any Securities in respect of which
liquidated damages are due cease to be Registrable Securities, all obligations
of the Company to pay such liquidated damages shall survive until such time as
such obligations in respect of such Securities shall have been satisfied in
full.

            3.    Registration Procedures.

            In connection with the obligations of the Company with respect to
Registration Statements pursuant to Sections 2.1 and 2.2 hereof, the Company
shall:

                  (a) prepare and file with the SEC a Registration Statement,
      within the relevant time period specified in Section 2, on the appropriate
      form under the 1933 Act, which form (i) shall be selected by the Company,
      (ii) shall, in the case of a Shelf Registration, be available for the sale
      of the Registrable Securities by the selling Holders thereof and, (iii)
      shall comply as to form in all material respects with the requirements of
      the 1933 Act and the Trust Indenture Act of 1939, as amended, and the
      rules and regulation of the SEC thereunder, and use all commercially
      reasonable efforts to cause such Registration Statement to become
      effective and remain effective in accordance with Section 2 hereof;

                  (b) prepare and file with the SEC such amendments and
      post-effective amendments to each Registration Statement as may be
      necessary under applicable law to keep such Registration Statement
      effective for the applicable period; and cause each Prospectus to be
      supplemented by any required prospectus supplement, and as so supplemented
      to be filed pursuant to Rule 424 under the 1933 Act and comply with the
      provisions of the 1933 Act, the 1934 Act and the rules and regulations
      thereunder applicable to them with respect to the disposition of all
      securities covered by each Registration Statement during the applicable
      period in accordance with the intended method or methods of distribution
      by the selling Holders thereof (including sales by any Participating
      Broker-Dealer);

                  (c) in the case of a Shelf Registration, (i) notify each
      Holder of Registrable Securities, at least five business days prior to
      filing, that a Shelf Registration Statement with respect to the
      Registrable Securities is being filed and advise such Holders that the
      distribution of Registrable Securities will be made in accordance with the
      methods selected by the Holders of a majority in principal amount of the
      Registrable Securities the Holders of which are participating in such
      Shelf Registration, (ii) furnish to each Holder of Registrable Securities
      and to each underwriter of an underwritten offering of Registrable
      Securities, if any, without charge, as many copies of each Prospectus,
      including each preliminary

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      Prospectus, and any amendment or supplement thereto and such other
      documents as such Holder or underwriter may reasonably request, and, if
      the Holder so requests, all exhibits in order to facilitate the public
      sale or other disposition of the Registrable Securities and (iii) be
      deemed to have consented to the use of the Prospectus or any amendment or
      supplement thereto by each of the selling Holders of Registrable
      Securities in connection with the offering and sale of the Registrable
      Securities covered by the Prospectus or any amendment or supplement
      thereto;

                  (d) use all commercially reasonable efforts to register or
      qualify the Registrable Securities under all applicable state securities
      or "blue sky" laws of such jurisdictions as any Holder of Registrable
      Securities covered by a Registration Statement and each underwriter of an
      underwritten offering of Registrable Securities shall reasonably request
      by the time the applicable Registration Statement is declared effective by
      the SEC, and do any and all other acts and things which may be reasonably
      necessary or advisable to enable each such Holder and such underwriter to
      consummate the disposition in each such jurisdiction of such Registrable
      Securities owned by such Holder; provided, however, that the Company shall
      not be required to (i) qualify as a foreign corporation or as a dealer in
      securities in any jurisdiction where it would not otherwise be required to
      qualify but for this Section 3(d) or (ii) take any action which would
      subject it to general service of process or taxation in any such
      jurisdiction where it is not then so subject;

                  (e) notify promptly each Holder of Registrable Securities
      under a Shelf Registration or any Participating Broker-Dealer who has
      notified the Company that it is utilizing the Exchange Offer Registration
      Statement as provided in paragraph (f) below and, if requested in writing
      by such Holder or Participating Broker-Dealer, confirm such advice in
      writing promptly (i) when a Registration Statement has become effective
      and when any post-effective amendments thereto become effective and any
      supplements thereto are filed, (ii) of any request by the SEC or any state
      securities authority for post-effective amendments to a Registration
      Statement and supplements to a Prospectus or for additional information
      after the Registration Statement has become effective, (iii) of the
      issuance by the SEC or any state securities authority of any stop order
      suspending the effectiveness of a Registration Statement or the initiation
      of any proceedings for that purpose, (iv) in the case of a Shelf
      Registration, if, between the effective date of a Registration Statement
      and the closing of any sale of Registrable Securities covered thereby, the
      representations and warranties of the Company contained in any
      underwriting agreement, securities sales agreement or other similar
      agreement, if any, relating to the offering cease to be true and correct
      in all material respects, (v) of the happening of any event or the
      discovery of any facts during any period in which a Registration Statement
      is effective which makes any statement made in such Registration Statement
      or the related Prospectus untrue in any material respect or which requires
      the making of any change in such Registration Statement or Prospectus in
      order to make the statements therein not misleading, (vi) of the receipt
      by the Company of any

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      notification with respect to the suspension of the qualification of the
      Registrable Securities or the Exchange Securities, as the case may be, for
      sale in any jurisdiction or the initiation or threatening of any
      proceeding for such purpose and (vii) of any determination by the Company
      that a post-effective amendment to such Registration Statement would be
      appropriate;

                  (f)   (A) in the case of the Exchange Offer Registration
      Statement, (i) include in the Exchange Offer Registration Statement a
      section entitled "Plan of Distribution" which section shall be reasonably
      acceptable to Merrill Lynch, Pierce, Fenner & Smith Incorporated ("Merrill
      Lynch"), on behalf of the Participating Broker-Dealers, and which shall
      contain a summary statement of the positions taken or policies made by the
      staff of the SEC with respect to the potential "underwriter" status of any
      broker-dealer that holds Registrable Securities acquired for its own
      account as a result of market-making activities or other trading
      activities and that will be the beneficial owner (as defined in Rule 13d-3
      under the Exchange Act) of Exchange Securities to be received by such
      broker-dealer in the Exchange Offer, whether such positions or policies
      have been publicly disseminated by the staff of the SEC or such positions
      or policies, in the reasonable judgment of Merrill Lynch on behalf of the
      Participating Broker-Dealers and its counsel, represent the prevailing
      views of the staff of the SEC, including a statement that any such
      broker-dealer who receives Exchange Securities for Registrable Securities
      pursuant to the Exchange Offer may be deemed a statutory underwriter and
      must deliver a prospectus meeting the requirements of the 1933 Act in
      connection with any resale of such Exchange Securities, (ii) furnish to
      each Participating Broker-Dealer who has delivered to the Company the
      written notice referred to in Section 3(e), without charge, as many copies
      of each Prospectus included in the Exchange Offer Registration Statement,
      including any preliminary prospectus, and any amendment or supplement
      thereto, as such Participating Broker-Dealer may reasonably request, (iii)
      be deemed to have consented to the use of the Prospectus forming part of
      the Exchange Offer Registration Statement or any amendment or supplement
      thereto, by any Person subject to the prospectus delivery requirements of
      the SEC, including all Participating Broker-Dealers, in connection with
      the sale or transfer of the Exchange Securities covered by the Prospectus
      or any amendment or supplement thereto and to have agreed to keep the
      Exchange Offer Registration Statement effective during the period of such
      use (up to a maximum of 180 days after the consummation of the Exchange
      Offer) and (iv) include in the transmittal letter or functionally
      equivalent documentation to be executed by or on behalf of an exchange
      offeree in order to participate in the Exchange Offer (x) a statement to
      the following effect:

            "If the exchange offeree is a broker-dealer holding Registrable
            Securities acquired for its own account as a result of market-making
            activities or other trading activities, it will deliver a prospectus
            meeting the requirements of the 1933 Act in connection with any
            resale

                                       12
<PAGE>

            of Exchange Securities received in respect of such Registrable
            Securities pursuant to the Exchange Offer." and

      (y) a statement to the effect that by a broker-dealer making the
      acknowledgment described in clause (x) and by delivering a Prospectus in
      connection with the exchange of Registrable Securities, the broker-dealer
      will not be deemed to admit that it is an underwriter within the meaning
      of the 1933 Act; and

                        (B) in the case of any Exchange Offer Registration
      Statement and solely upon the written request of the Representative,
      deliver to the Initial Purchasers on behalf of the Participating
      Broker-Dealers, prior to the commencement of the Exchange Offer (i) an
      opinion of counsel or opinions of counsel substantially to the effect set
      forth in Exhibit A, (ii) officers' certificates substantially in the form
      customarily delivered in a public offering of debt securities and (iii) a
      comfort letter or comfort letters in customary form to the extent
      permitted by Statement on Auditing Standards No. 72 of the American
      Institute of Certified Public Accountants (or if such a comfort letter is
      not permitted, an agreed upon procedures letter in customary form) from
      the Company's independent certified public accountants (and, if necessary,
      any other independent certified public accountants of any subsidiary of
      the Company or of any business acquired by the Company for which financial
      statements are, or are required to be, included in the Registration
      Statement) at least as broad in scope and coverage as the comfort letter
      or comfort letters delivered to the Initial Purchasers in connection with
      the initial sale of the Securities to the Initial Purchasers;

                  (g) (i) in the case of an Exchange Offer, furnish counsel for
      the Initial Purchasers and (ii) in the case of a Shelf Registration,
      furnish counsel for the Holders of Registrable Securities copies of any
      comment letters received from the SEC or any other request by the SEC or
      any state securities authority for amendments or supplements to a
      Registration Statement and Prospectus or for additional information;

                  (h) make all commercially reasonable efforts to obtain the
      withdrawal of any order suspending the effectiveness of a Registration
      Statement at the earliest possible moment;

                  (i) in the case of a Shelf Registration, furnish to each
      Holder of Registrable Securities, and each underwriter, if any, without
      charge, at least one conformed copy of each Registration Statement and any
      post-effective amendment thereto, including financial statements and
      schedules (without documents incorporated therein by reference and all
      exhibits thereto, unless requested);

                  (j) in the case of a Shelf Registration, cooperate with the
      selling Holders of Registrable Securities to facilitate the timely
      preparation and delivery of certificates representing Registrable
      Securities to be sold and not

                                       13
<PAGE>

      bearing any restrictive legends; and enable such Registrable Securities to
      be in such denominations (consistent with the provisions of the Indenture)
      and registered in such names as the selling Holders or the underwriters,
      if any, may reasonably request at least five business days prior to the
      closing of any sale of Registrable Securities;

                  (k) upon the occurrence of any event or the discovery of any
      facts, each as contemplated by Sections 3(e)(v) and 3(e)(vi) hereof, as
      promptly as practicable after the occurrence of such an event, use all
      commercially reasonable efforts to prepare a post-effective amendment to
      the Registration Statement, a supplement to the related Prospectus or an
      amendment to any document incorporated therein by reference or file any
      other required document so that, as thereafter delivered to the purchasers
      of the Registrable Securities or Participating Broker-Dealers, the
      Prospectus will not contain at the time of such delivery any untrue
      statement of a material fact or omit to state a material fact necessary to
      make the statements therein, in light of the circumstances under which
      they were made, not misleading. At such time as such public disclosure is
      otherwise made or the Company determines that such disclosure is not
      necessary, in each case to correct any misstatement of a material fact or
      to include any omitted material fact, the Company agrees promptly to
      notify each Holder of such determination and to furnish each Holder such
      number of copies of the Prospectus as amended or supplemented, as such
      Holder may reasonably request;

                  (l) in the case of a Shelf Registration, a reasonable time
      prior to the filing of any Registration Statement, any Prospectus, any
      amendment to a Registration Statement or amendment or supplement to a
      Prospectus (excluding, in any case, any document which is to be
      incorporated by reference into a Registration Statement or a Prospectus
      after the initial filing of a Registration Statement), provide copies of
      such document to the Holders participating in such Shelf Registration and
      make such representatives of the Company as shall be reasonably requested
      by the Holders of a majority in principal amount of the Registrable
      Securities the Holders of which are participating in such Shelf
      Registration, available for discussion of such document;

                  (m) obtain a CUSIP number for all Exchange Securities, Private
      Exchange Securities or Registrable Securities, as the case may be, not
      later than the effective date of a Registration Statement, and provide the
      Trustee with printed certificates for the Exchange Securities, Private
      Exchange Securities or the Registrable Securities, as the case may be, in
      a form eligible for deposit with the Depositary;

                  (n) (i) use all commercially reasonable efforts to cause the
      Indenture to be qualified under the TIA in connection with the
      registration of the Exchange Securities or Registrable Securities, as the
      case may be, (ii) cooperate with the Trustee and the Holders to effect
      such changes to the Indenture as may be required for the Indenture to be
      so qualified in accordance with the terms of the TIA and (iii) execute,
      and use all commercially reasonable efforts to cause the

                                       14
<PAGE>

      Trustee to execute, all documents which may be required to effect such
      changes, and all other forms and documents required to be filed with the
      SEC to enable the Indenture to be so qualified in a timely manner;

                  (o)   in the case of a Shelf Registration and at the request
      of the Holders of a majority in principal amount of the Registrable
      Securities the Holders of which are participating in such Shelf
      Registration, enter into agreements (including underwriting agreements)
      and take all other customary and appropriate actions in order to expedite
      or facilitate the disposition of such Registrable Securities and in such
      connection whether or not an underwriting agreement is entered into and
      whether or not the registration is an underwritten registration:

                        (i) make such representations and warranties to such
            Holders and the underwriters, if any, in form, substance and scope
            as are customarily made by issuers to underwriters in similar
            underwritten offerings as may be reasonably requested by them;

                        (ii) obtain opinions of counsel to the Company and
            updates thereof (which counsel and opinions (in form, scope and
            substance) shall be reasonably satisfactory to the managing
            underwriters, if any, and the holders of a majority in principal
            amount of the Registrable Securities being sold) addressed to each
            selling Holder and the underwriters, if any, covering the matters
            customarily covered in opinions requested in sales of securities or
            underwritten offerings and such other matters as may be reasonably
            requested by such Holders and underwriters;

                        (iii) obtain "cold comfort" letters and updates thereof
            from the Company's independent certified public accountants (and, if
            necessary, any other independent certified public accountants of any
            subsidiary of the Company or of any business acquired by the Company
            for which financial statements are, or are required to be, included
            in the Registration Statement) addressed to the underwriters, if
            any, and use reasonable efforts to have such letter addressed to the
            selling Holders of Registrable Securities (to the extent consistent
            with Statement on Auditing Standards No. 72 of the American
            Institute of Certified Public Accounts), such letters to be in
            customary form and covering matters of the type customarily covered
            in "cold comfort" letters to underwriters in connection with similar
            underwritten offerings;

                        (iv) enter into a securities sales agreement with the
            Holders and an agent of the Holders providing for, among other
            things, the appointment of such agent for the selling Holders for
            the purpose of soliciting purchases of Registrable Securities, which
            agreement shall be in form, substance and scope customary for
            similar offerings;

                                       15
<PAGE>

                        (v) if an underwriting agreement is entered into, cause
            the same to set forth indemnification provisions and procedures
            substantially equivalent to the indemnification provisions and
            procedures set forth in Section 4 hereof with respect to the
            underwriters and all other parties to be indemnified pursuant to
            said Section or, at the request of any underwriters, in the form
            customarily provided to such underwriters in similar types of
            transactions; and

                        (vi) deliver such documents and certificates as may be
            reasonably requested and as are customarily delivered in similar
            offerings to the Holders of the Registrable Securities being sold
            and the managing underwriters, if any.

      The above shall be done at (i) the effectiveness of such Registration
      Statement (and each post-effective amendment thereto) and (ii) each
      closing under any underwriting or similar agreement as and to the extent
      required thereunder;

                  (p)   in the case of a Shelf Registration or if a Prospectus
      is required to be delivered by any Participating Broker-Dealer in the case
      of an Exchange Offer, make available for inspection by representatives of
      the Holders of the Registrable Securities, any underwriters participating
      in any disposition pursuant to a Shelf Registration Statement, any
      Participating Broker-Dealer and any counsel or accountant retained by any
      of the foregoing, all financial and other records, pertinent corporate
      documents and properties of the Company reasonably requested by any such
      persons, and cause the respective officers, directors, employees, and any
      other agents of the Company to supply all information reasonably requested
      by any such representative, underwriter, special counsel or accountant in
      connection with a Registration Statement, and make such representatives of
      the Company available for discussion of such documents as shall be
      reasonably requested by the Initial Purchasers;

                  (q)   (i) in the case of an Exchange Offer Registration
      Statement and upon the written request of the Representative, a reasonable
      time prior to the filing of any Exchange Offer Registration Statement, any
      Prospectus forming a part thereof, any amendment to an Exchange Offer
      Registration Statement or amendment or supplement to such Prospectus,
      provide copies of such document to the Representative and/or counsel to
      the Initial Purchasers and make such changes in any such document prior to
      the filing thereof as the Representative or such counsel may reasonably
      request and, except as otherwise required by applicable law, not file any
      such document in a form to which the Representative or counsel to the
      Initial Purchasers shall not have previously been advised and furnished a
      copy of or to which the Representative or such counsel shall reasonably
      object, and make the representatives of the Company available for
      discussion of such documents as shall be reasonably requested by the
      Representative; and

                                       16
<PAGE>

                  (ii) in the case of a Shelf Registration, a reasonable time
      prior to filing any Shelf Registration Statement, any Prospectus forming a
      part thereof, any amendment to such Shelf Registration Statement or
      amendment or supplement to such Prospectus, provide copies of such
      document to the Holders of Registrable Securities, to counsel for such
      Holders and to the underwriter or underwriters of an underwritten offering
      of Registrable Securities, if any, and, upon the written request of the
      Representative, to the Representative and/or counsel to the Initial
      Purchasers, make such changes in any such document prior to the filing
      thereof as the Initial Purchasers, counsel to the Holders of Registrable
      Securities or the underwriter or underwriters shall reasonably request and
      not file any such document in a form to which the Representative, the
      Majority Holders, counsel for the Holders of Registrable Securities or any
      underwriter shall not have previously been advised and furnished a copy of
      or to which the Representative, the Majority Holders, counsel to the
      Holders of Registrable Securities or any underwriter shall reasonably
      object, and make the representatives of the Company available for
      discussion of such document as shall be reasonably requested by the
      Representative, the Majority Holders, counsel for the Holders of
      Registrable Securities or any underwriter;

                  (r) in the case of a Shelf Registration, use all commercially
      reasonable efforts to cause all Registrable Securities to be listed on any
      securities exchange on which similar debt securities issued by the Company
      are then listed if requested by the Majority Holders, or if requested by
      the underwriter or underwriters of an underwritten offering of Registrable
      Securities, if any;

                  (s) in the case of a Shelf Registration, use all commercially
      reasonable efforts to cause the Registrable Securities to be rated by the
      appropriate rating agencies, if so requested by the Majority Holders, or
      if requested by the underwriter or underwriters of an underwritten
      offering of Registrable Securities, if any;

                  (t) otherwise comply with all applicable rules and regulations
      of the SEC and make available to its security holders, as soon as
      reasonably practicable, an earning statement covering at least 12 months
      which shall satisfy the provisions of Section 11(a) of the 1933 Act and
      Rule 158 thereunder; and

                  (u) cooperate and assist in any filings required to be made
      with the NASD and, in the case of a Shelf Registration, in the performance
      of any due diligence investigation by any underwriter and its counsel
      (including any "qualified independent underwriter" that is required to be
      retained in accordance with the rules and regulations of the NASD).

            Each Holder will be deemed to have agreed that, upon receipt of any
notice from the Company of the happening of any event or the discovery of any
facts, each of the kind described in Section 3(e)(v) or 3(e)(vi) (in the event
that such notice pursuant to 3(e)(vi) relates to the jurisdiction in which such
Holder plans to dispose of Registrable Securities) hereof, such Holder will
forthwith discontinue disposition of

                                       17
<PAGE>

Registrable Securities pursuant to a Registration Statement until such Holder's
receipt of the copies of the supplemented or amended Prospectus contemplated by
Section 3(k) hereof, and, if so directed by the Company, such Holder will
deliver to the Company (at its expense) all copies in such Holder's possession,
other than permanent file copies then in such Holder's possession, of the
Prospectus covering such Registrable Securities current at the time of receipt
of such notice.

            In the event that the Company fails to effect the Exchange Offer or
file any Shelf Registration Statement and maintain the effectiveness of any
Shelf Registration Statement as provided herein (other than by reason of a
prohibition, condition or other requirement not in effect at the date hereof
imposed by any statute or governmental regulation), the Company shall not file
any Registration Statement with respect to any securities (within the meaning of
Section 2(1) of the 1933 Act) of the Company other than Registrable Securities.

            If any of the Registrable Securities covered by any Shelf
Registration Statement are to be sold in an underwritten offering, the
underwriter or underwriters and manager or managers that will manage such
offering will be selected by the Majority Holders of such Registrable Securities
included in such offering and shall be reasonably acceptable to the Company. No
Holder of Registrable Securities may participate in any underwritten
registration hereunder unless such Holder (a) agrees to sell such Holder's
Registrable Securities on the basis provided in any underwriting arrangements
approved by the persons entitled hereunder to approve such arrangements and (b)
completes and executes all questionnaires, powers of attorney, indemnities,
underwriting agreements and other documents required under the terms of such
underwriting arrangements.

            In the case of a Shelf Registration Statement, the Company may
require each Holder of Registrable Securities to furnish to the Company, and
update, such information regarding such Holder and the proposed distribution by
such Holder as the Company may from time to time reasonably request. Such
information may include such Holder's name and address and any relationships
between such Holder and the Company, any of the Initial Purchasers or any
underwriter proposing to participate in such proposed distribution. In order to
obtain such information, the Company shall, at least fifteen business days prior
to the filing of such Shelf Registration Statement, commence commercially
reasonable efforts, in cooperation with the Depositary and the Initial
Purchasers, (a) to inform the Holders of Registrable Securities that a Shelf
Registration Statement is being filed and (b) to specify the information
regarding such Holders which the Company requires in connection with the
preparation thereof.

            Anything in this Agreement to the contrary notwithstanding, any
Holder of Registrable Securities which shall not have timely furnished to the
Company the information so requested with respect to any Shelf Registration
Statement:

                  (a)   shall not be entitled to have the Registrable Securities
      held by it covered by such Shelf Registration Statement or to receive
      copies of such Shelf Registration Statement or the Prospectus relating
      thereto;

                                       18
<PAGE>

                  (b)   shall not be entitled to any liquidated damages
      contemplated in clause (d) or (e) of the first sentence in the first
      paragraph, or in the second paragraph, of Section 2.5 hereof;

                  (c)   shall not be entitled to receive any notices from the
      Company as provided in this Section 3 or elsewhere in this Agreement; and

                  (d)   shall not otherwise be deemed a Holder of Registrable
      Securities for purposes of this Agreement with respect to such Shelf
      Registration Statement.

            All Holders of Registrable Securities, by their payment for and
acceptance of such Securities, shall be deemed to have consented and agreed to
the terms and provisions of this Agreement including, without limitation, the
terms and provisions of this Section 3.

            4.    Indemnification; Contribution.

            (a)   The Company agrees to indemnify and hold harmless the Initial
Purchasers, each Holder, each Participating Broker-Dealer, each Person who
participates as an underwriter (any such Person being an "Underwriter") and each
Person, if any, who controls any Holder or Underwriter within the meaning of
Section 15 of the 1933 Act or Section 20 of the 1934 Act as follows:

                        (i) against any and all loss, liability, claim, damage
            and expense whatsoever, as incurred, arising out of any untrue
            statement or alleged untrue statement of a material fact contained
            in any Registration Statement (or any amendment or supplement
            thereto) pursuant to which Exchange Securities or Registrable
            Securities were registered under the 1933 Act, including all
            documents incorporated therein by reference, or the omission or
            alleged omission therefrom of a material fact required to be stated
            therein or necessary to make the statements therein not misleading,
            or arising out of any untrue statement or alleged untrue statement
            of a material fact contained in any Prospectus (or any amendment or
            supplement thereto) or the omission or alleged omission therefrom of
            a material fact necessary in order to make the statements therein,
            in the light of the circumstances under which they were made, not
            misleading;

                        (ii) against any and all loss, liability, claim, damage
            and expense whatsoever, as incurred, to the extent of the aggregate
            amount paid in settlement of any litigation, or any investigation or
            proceeding by any governmental agency or body, commenced or
            threatened, or of any claim whatsoever based upon any such untrue
            statement or omission, or any such alleged untrue statement or
            omission; provided that (subject to Section 4(d) below) any such
            settlement is effected with the written consent of the Company; and

                                       19
<PAGE>

                        (iii) against any and all expense whatsoever, as
            incurred (including the fees and disbursements of counsel chosen by
            any indemnified party), reasonably incurred in investigating,
            preparing or defending against any litigation, or any investigation
            or proceeding by any governmental agency or body, commenced or
            threatened, or any claim whatsoever based upon any such untrue
            statement or omission, or any such alleged untrue statement or
            omission, to the extent that any such expense is not paid under
            subparagraph (i) or (ii) above;

provided, however, that this indemnity agreement shall not apply to any loss,
liability, claim, damage or expense to the extent arising out of any untrue
statement or omission or alleged untrue statement or omission made in reliance
upon and in conformity with written information furnished to the Company by the
Holder or Underwriter expressly for use in a Registration Statement (or any
amendment thereto) or any Prospectus (or any amendment or supplement thereto);
and provided, further, that this indemnity agreement shall not inure to the
benefit of any Underwriter or any person who controls such Underwriter on
account of any such loss, liability, claim, damage or expense arising out of any
such defect or alleged defect in any preliminary prospectus if a copy of the
Prospectus (exclusive of the documents incorporated by reference therein) shall
not have been given or sent by such Underwriter with or prior to the written
confirmation of the sale involved to the extent that (i) the Prospectus would
have cured such defect or alleged defect and (ii) sufficient quantities of the
Prospectus were timely made available to such Underwriter.

            (b)   Each Holder severally, but not jointly, agrees to indemnify
and hold harmless the Company, the Initial Purchasers, each Underwriter and the
other selling Holders, and each of their respective directors and officers, and
each Person, if any, who controls the Company, the Initial Purchasers, any
Underwriter or any other selling Holder within the meaning of Section 15 of the
1933 Act or Section 20 of the 1934 Act, against any and all loss, liability,
claim, damage and expense described in the indemnity contained in Section 4(a)
hereof, as incurred, but only with respect to untrue statements or omissions, or
alleged untrue statements or omissions, made in the Shelf Registration Statement
(or any amendment thereto) or any Prospectus included therein (or any amendment
or supplement thereto) in reliance upon and in conformity with written
information with respect to such Holder furnished to the Company by such Holder
expressly for use in the Shelf Registration Statement (or any amendment thereto)
or such Prospectus (or any amendment or supplement thereto); provided, however,
that no such Holder shall be liable for any claims hereunder in excess of the
amount of net proceeds received by such Holder from the sale of Registrable
Securities pursuant to such Shelf Registration Statement.

            (c)   Each indemnified party shall give notice as promptly as
reasonably practicable to each indemnifying party of any action or proceeding
commenced against it in respect of which indemnity may be sought hereunder, but
failure so to notify an indemnifying party shall not relieve such indemnifying
party from any liability hereunder to the extent it is not materially prejudiced
as a result thereof and in any event shall not relieve it from any liability
which it may have otherwise than on account of this

                                       20
<PAGE>

indemnity agreement. An indemnifying party may participate at its own expense in
the defense of such action; provided, however, that counsel to the indemnifying
party shall not (except with the consent of the indemnified party) also be
counsel to the indemnified party. In no event shall the indemnifying party or
parties be liable for the fees and expenses of more than one counsel (in
addition to any local counsel) separate from their own counsel for all
indemnified parties in connection with any one action or separate but similar or
related actions in the same jurisdiction arising out of the same general
allegations or circumstances. No indemnifying party shall, without the prior
written consent of the indemnified parties, settle or compromise or consent to
the entry of any judgment with respect to any litigation, or any investigation
or proceeding by any governmental agency or body, commenced or threatened, or
any claim whatsoever in respect of which indemnification or contribution could
be sought under this Section 4 (whether or not the indemnified parties are
actual or potential parties thereto), unless such settlement, compromise or
consent (i) includes an unconditional release of each indemnified party from all
liability arising out of such litigation, investigation, proceeding or claim and
(ii) does not include a statement as to or an admission of fault, culpability or
a failure to act by or on behalf of any indemnified party.

            (d) If at any time an indemnified party shall have requested an
indemnifying party to reimburse the indemnified party for fees and expenses of
counsel, such indemnifying party agrees that it shall be liable for any
settlement of the nature contemplated by Section 4(a)(ii) effected without its
written consent if (i) such settlement is entered into more than 45 days after
receipt by such indemnifying party of the aforesaid request, (ii) such
indemnifying party shall have received notice of the terms of such settlement at
least 30 days prior to such settlement being entered into and (iii) such
indemnifying party shall not have reimbursed such indemnified party in
accordance with such request prior to the date of such settlement.

            (e) If the indemnification provided for in this Section 4 is for any
reason unavailable to or insufficient to hold harmless an indemnified party in
respect of any losses, liabilities, claims, damages or expenses referred to
therein, then each indemnifying party shall contribute to the aggregate amount
of such losses, liabilities, claims, damages and expenses incurred by such
indemnified party, as incurred, in such proportion as is appropriate to reflect
the relative fault of the Company on the one hand and the Holders and the
Initial Purchasers on the other hand in connection with the statements or
omissions which resulted in such losses, liabilities, claims, damages or
expenses, as well as any other relevant equitable considerations.

            The relative fault of the Company on the one hand and the Holders
and the Initial Purchasers on the other hand shall be determined by reference
to, among other things, whether any such untrue or alleged untrue statement of a
material fact or omission or alleged omission to state a material fact relates
to information supplied by the Company, the Holders or the Initial Purchasers
and the parties' relative intent, knowledge, access to information and
opportunity to correct or prevent such statement or omission.

                                       21
<PAGE>

            The Company, the Holders and the Initial Purchasers agree that it
would not be just and equitable if contribution pursuant to this Section 4 were
determined by pro rata allocation (even if the Initial Purchasers were treated
as one entity for such purpose) or by any other method of allocation which does
not take account of the equitable considerations referred to above in this
Section 4. The aggregate amount of losses, liabilities, claims, damages and
expenses incurred by an indemnified party and referred to above in this Section
4 shall be deemed to include any legal or other expenses reasonably incurred by
such indemnified party in investigating, preparing or defending against any
litigation, or any investigation or proceeding by any governmental agency or
body, commenced or threatened, or any claim whatsoever based upon any such
untrue or alleged untrue statement or omission or alleged omission.

            Notwithstanding the provisions of this Section 4, no Initial
Purchaser shall be required to contribute any amount in excess of the amount by
which the total price at which the Securities sold by it were offered exceeds
the amount of any damages which such Initial Purchaser has otherwise been
required to pay by reason of such untrue or alleged untrue statement or omission
or alleged omission.

            No Person guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the 1933 Act) shall be entitled to contribution from any
Person who was not guilty of such fraudulent misrepresentation.

            For purposes of this Section 4, each Person, if any, who controls an
Initial Purchaser or Holder within the meaning of Section 15 of the 1933 Act or
Section 20 of the 1934 Act shall have the same rights to contribution as such
Initial Purchaser or Holder, and each director of the Company, and each Person,
if any, who controls the Company within the meaning of Section 15 of the 1933
Act or Section 20 of the 1934 Act shall have the same rights to contribution as
the Company. The Initial Purchasers' respective obligations to contribute
pursuant to this Section 7 are several in proportion to the principal amount of
Securities set forth opposite their respective names in Schedule A to the
Purchase Agreement and not joint.

            5.    Miscellaneous.

            5.1   Rule 144 and Rule 144A. So long as the Company is subject to
the reporting requirements of Section 13 or 15 of the 1934 Act, the Company
covenants that it will file the reports required to be filed by it under the
1933 Act and Section 13(a) or 15(d) of the 1934 Act and the rules and
regulations adopted by the SEC thereunder. If the Company ceases to be so
required to file such reports, the Company covenants that it will upon the
request of any Holder of Registrable Securities (a) make publicly available such
information as is necessary to permit sales pursuant to Rule 144 under the 1933
Act, (b) deliver such information to a prospective purchaser as is necessary to
permit sales pursuant to Rule 144A under the 1933 Act and it will take such
further action as any Holder of Registrable Securities may reasonably request,
and (c) take such further action that is reasonable in the circumstances, in
each case, to the extent required from time to time to enable such Holder to
sell its Registrable Securities without registration under the 1933 Act within
the limitation of the exemptions provided by (i) Rule 144 under the 1933

                                       22
<PAGE>

Act, as such Rule may be amended from time to time, (ii) Rule 144A under the
1933 Act, as such Rule may be amended from time to time, or (iii) any similar
rules or regulations hereafter adopted by the SEC. Upon the request of any
Holder of Registrable Securities, the Company will deliver to such Holder a
written statement as to whether it has complied with such requirements.

            5.2 No Inconsistent Agreements. The Company has not entered into and
the Company will not after the date of this Agreement enter into any agreement
which is inconsistent with the rights granted to the Holders of Registrable
Securities in this Agreement or otherwise conflicts with the provisions hereof.
The rights granted to the Holders hereunder do not and will not for the term of
this Agreement in any way conflict with the rights granted to the holders of the
Company's other issued and outstanding securities under any such agreements.

            5.3 Amendments and Waivers. The provisions of this Agreement,
including the provisions of this sentence, may not be amended, modified or
supplemented, and waivers or consents to departures from the provisions hereof
may not be given unless the Company has obtained the written consent of Holders
of at least a majority in aggregate principal amount of the outstanding
Registrable Securities affected by such amendment, modification, supplement,
waiver or departure.

            5.4 Notices. All notices and other communications provided for or
permitted hereunder shall be made in writing by hand delivery, registered
first-class mail, telex, telecopier, or any courier guaranteeing overnight
delivery (a) if to a Holder, at the most current address given by such Holder to
the Company by means of a notice given in accordance with the provisions of this
Section 5.4, which address initially is the address set forth in the Purchase
Agreement with respect to the Initial Purchasers; and (b) if to the Company,
initially at the Company's address set forth in the Purchase Agreement, and
thereafter at such other address of which notice is given in accordance with the
provisions of this Section 5.4.

            All such notices and communications shall be deemed to have been
duly given: at the time delivered by hand, if personally delivered; two business
days after being deposited in the mail, postage prepaid, if mailed; when
answered back, if telexed; when receipt is acknowledged, if telecopied; and on
the next business day if timely delivered to an air courier guaranteeing
overnight delivery.

            Copies of all such notices, demands, or other communications shall
be concurrently delivered by the person giving the same to the Trustee under the
Indenture, at the address specified in such Indenture.

            5.5 Successor and Assigns. This Agreement shall inure to the benefit
of and be binding upon the successors, assigns and transferees of each of the
parties, including, without limitation and without the need for an express
assignment, subsequent Holders; provided, however, that nothing herein shall be
deemed to permit any assignment, transfer or other disposition of Registrable
Securities in violation of the terms of the Purchase Agreement or the Indenture.
If any transferee of any Holder shall

                                       23
<PAGE>

acquire Registrable Securities, in any manner, whether by operation of law or
otherwise, such Registrable Securities shall be held subject to all of the terms
of this Agreement, and by taking and holding such Registrable Securities such
person shall be conclusively deemed to have agreed to be bound by and to perform
all of the terms and provisions of this Agreement, including the restrictions on
resale set forth in this Agreement and, if applicable, the Purchase Agreement,
and such person shall be entitled to receive the benefits hereof.

            5.6 Third Party Beneficiaries. The Initial Purchasers (even if the
Initial Purchasers are not Holders of Registrable Securities) shall be third
party beneficiaries to the agreements made hereunder between the Company, on the
one hand, and the Holders, on the other hand, and shall have the right to
enforce such agreements directly to the extent they deem such enforcement
necessary or advisable to protect their rights or the rights of Holders
hereunder. Each Holder of Registrable Securities shall be a third party
beneficiary to the agreements made hereunder between the Company, on the one
hand, and the Initial Purchasers, on the other hand, and shall have the right to
enforce such agreements directly to the extent it deems such enforcement
necessary or advisable to protect its rights hereunder.

            5.7 Specific Enforcement. Without limiting the remedies available to
the Initial Purchasers and the Holders, the Company acknowledges that any
failure by the Company to comply with its obligations under Sections 2.1 through
2.4 hereof may result in material irreparable injury to the Initial Purchasers
or the Holders for which there is no adequate remedy at law, that it would not
be possible to measure damages for such injuries precisely and that, in the
event of any such failure, the Initial Purchasers or any Holder may obtain such
relief as may be required to specifically enforce the Company's obligations
under Sections 2.1 through 2.4 hereof.

            5.8 Restriction on Resales. Until the expiration of two years after
the Closing Date, the Company will not, and will cause its "affiliates" (as such
term is defined in Rule 144(a)(1) under the 1933 Act) not to, resell any
Securities which are "restricted securities" (as such term is defined under Rule
144(a)(3) under the 1933 Act) that have been reacquired by any of them and shall
immediately upon any purchase of any such Securities submit such Securities to
the Trustee for cancellation.

            5.9 Counterparts. This Agreement may be executed in any number of
counterparts and by the parties hereto in separate counterparts, each of which
when so executed shall be deemed to be an original and all of which taken
together shall constitute one and the same agreement.

            5.10 Headings. The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

            5.11 GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAW OF THE STATE OF NEW YORK WITHOUT REGARD TO
THE PRINCIPLES OF CONFLICT OF LAWS THEREOF.

                                       24
<PAGE>

            5.12 Severability. In the event that any one or more of the
provisions contained herein, or the application thereof in any circumstance, is
held invalid, illegal or unenforceable, the validity, legality and
enforceability of any such provision in every other respect and of the remaining
provisions contained herein shall not be affected or impaired thereby.

                                       25
<PAGE>

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

                                           SIERRA PACIFIC RESOURCES

                                           By: _________________________________
                                               Name:
                                               Title:
Confirmed and accepted as
  of the date first above written:

MERRILL LYNCH, PIERCE, FENNER & SMITH
             INCORPORATED,

As Representative of the Initial Purchasers

By: _______________________________________
    Name:
    Title:

                 Signature Page to Registration Rights Agreement

                                       26
<PAGE>

                                                                       Exhibit A

                         CONTENTS OF OPINION OF COUNSEL

            1. The Exchange Offer Registration Statement and the Prospectus
(other than the financial statements, notes or schedules thereto and other
financial data and supplemental schedules included or incorporated by reference
therein or omitted therefrom and the Form T-1, as to which such counsel need
express no opinion), comply as to form in all material respects with the
requirements of the 1933 Act and the applicable rules and regulations
promulgated under the 1933 Act.

            2. Nothing has come to our attention that would lead us to believe
that the Exchange Offer Registration Statement (except for financial statements
and schedules and other financial data included therein as to which we make no
statement), when it became effective, contained an untrue statement of a
material fact or omitted to state a material fact required to be stated therein
or necessary to make the statements therein not misleading or that the
Prospectus, as amended or supplemented (except for financial statements and
schedules and other financial data included therein, as to which such counsel
need make no statement), at the date of such opinion includes an untrue
statement of a material fact or omits to state a material fact necessary in
order to make the statements therein, in the light of the circumstances under
which they were made, not misleading.

                                       A-1