Document:

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                                                                     EXHIBIT 4.1

                       PUBLIC SERVICE COMPANY OF COLORADO

          4.875 % First Collateral Trust Bonds, Series No. 11 due 2013

                          REGISTRATION RIGHTS AGREEMENT

                                                              New York, New York
                                                                  March 14, 2003

Banc One Capital Markets, Inc.
1 Bank One Plaza
Chicago, Illinois 60670

UBS Warburg LLC
677 Washington Boulevard
Stamford, Connecticut 06901

As Representatives of the Initial Purchasers

Ladies and Gentlemen:

         Public Service Company of Colorado, a corporation organized under the
laws of the State of Colorado (the "Company"), proposes to issue and sell to
certain purchasers (the "Initial Purchasers") the Company's 4.875% First
Collateral Trust Bonds, Series No. 11 due 2013 (the "Securities"), upon the
terms set forth in a purchase agreement dated as of March 7, 2003 (the "Purchase
Agreement"), relating to the initial placement of the Securities (the "Initial
Placement"). To induce the Initial Purchasers to enter into the Purchase
Agreement and to satisfy a condition of your obligations thereunder, the Company
agrees with you for your benefit and the benefit of the holders from time to
time of the Securities (including the Initial Purchasers) (each a "Holder" and,
together, the "Holders"), as follows:

         1.       Definitions. Each of the capitalized terms used herein without
definition shall have the meaning set forth in the Purchase Agreement. As used
in this Agreement, the following capitalized defined terms shall have the
following meanings:

                  "Act" shall mean the Securities Act of 1933, as amended, and
the rules and regulations of the Commission promulgated thereunder.

                  "Affiliate" of any specified Person shall mean any other
Person that, directly or indirectly, is in control of, is controlled by, or is
under common control with, such specified Person. For purposes of this
definition, control of a Person shall mean the power, direct or indirect, to
direct or cause the direction of the management and policies of such Person
whether by contract or otherwise; and the terms "controlling" and "controlled"
shall have meanings correlative to the foregoing.

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                  "Broker-Dealer" shall mean any broker or dealer registered as
such under the Exchange Act.

                  "Business Day" shall mean any day other than a Saturday, a
Sunday or a legal holiday or a day on which banking institutions or trust
companies are authorized or obligated by law to close in New York City.

                  "Commission" shall mean the Securities and Exchange
Commission.

                  "Consummation Deadline" shall have the meaning set forth in
Section 2(a) hereof.

                  "Exchange Act" shall mean the Securities Exchange Act of 1934,
as amended, and the rules and regulations of the Commission promulgated
thereunder.

                  "Exchange Offer Registration Period" shall mean the 210-day
period following the consummation of the Registered Exchange Offer, exclusive of
any period during which any stop order shall be in effect suspending the
effectiveness of the Exchange Offer Registration Statement.

                  "Exchange Offer Registration Statement" shall mean a
registration statement of the Company on an appropriate form under the Act with
respect to the Registered Exchange Offer, all amendments and supplements to such
registration statement, including post-effective amendments thereto, in each
case including the Prospectus contained therein, all exhibits thereto and all
material incorporated by reference therein.

                  "Exchanging Dealer" shall mean any Holder (which may include
any Initial Purchaser) that is a Broker-Dealer and elects to exchange any
Securities that it acquired for its own account as a result of market-making
activities or other trading activities (but not directly from the Company or any
Affiliate of the Company) for New Securities.

                  "Filing Deadline" shall have the meaning set forth in the
Section 2(a) hereof.

                  "Final Memorandum" shall have the meaning set forth in the
Purchase Agreement.

                  "Holder" shall have the meaning set forth in the preamble
hereto.

                  "Indenture" shall mean the Company's Indenture, dated as of
October 1, 1993 (the "Original Indenture") to U.S. Bank Trust National
Association, as successor trustee (the "Trustee"), as heretofore supplemented
including the supplemental indenture creating the Bonds, as the same may be
further amended and supplemented from time to time in accordance with the terms
thereof.

                  "Initial Placement" shall have the meaning set forth in the
preamble hereto.

                  "Initial Purchaser" shall have the meaning set forth in the
preamble hereto.

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                  "Liquidated Damages" has the meaning set forth in Section 8(a)
hereof.

                  "Losses" shall have the meaning set forth in Section 6(d)
hereof.

                  "Majority Holders" shall mean the Holders of a majority of the
aggregate principal amount of Securities registered under a Registration
Statement.

                  "Managing Underwriters" shall mean the investment banker or
investment bankers and manager or managers that shall administer an underwritten
offering of the Securities offered pursuant to a Shelf Registration Statement.

                  "New Securities" shall mean debt securities of the Company
identical in all material respects to the Securities (except that the interest
rate step-up provisions and the transfer restrictions shall be modified or
eliminated, as appropriate) and to be issued under the Indenture.

                  "Prospectus" shall mean the prospectus included in any
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 430A under the Act), as
amended or supplemented by any prospectus supplement, with respect to the terms
of the offering of any portion of the Securities or the New Securities covered
by such Registration Statement, and all amendments and supplements thereto and
all material incorporated by reference therein.

                  "Purchase Agreement" shall have the meaning set forth in the
preamble hereto.

                  "Registered Exchange Offer" shall mean the proposed offer of
the Company to issue and deliver to the Holders of the Securities that are not
prohibited by any law or policy of the Commission from participating in such
offer, in exchange for the Securities, a like aggregate principal amount of the
New Securities.

                  "Registration Default" has the meaning set forth in Section
8(a) hereof.

                  "Registration Statement" shall mean any Exchange Offer
Registration Statement or Shelf Registration Statement that covers any of the
Securities or the New Securities pursuant to the provisions of this Agreement,
any 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.

                  "Securities" shall have the meaning set forth in the preamble
hereto.

                  "Shelf Registration" shall mean a registration effected
pursuant to Section 3 hereof.

                  "Shelf Registration Period" has the meaning set forth in
Section 3(b) hereof.

                  "Shelf Registration Statement" shall mean a "shelf"
registration statement of the Company pursuant to the provisions of Section 3
hereof which covers some or all of the

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Securities or New Securities, as applicable, on an appropriate form under Rule
415 under the Act, or any similar rule that may be adopted by the Commission,
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.

         2.       Registered Exchange Offer.

                  (a)      The Company shall prepare and, not later than 90 days
following the date of the original issuance of the Securities (or if such 90th
day is not a Business Day, the next succeeding Business Day, such day being a
"Filing Deadline"), shall file with the Commission the Exchange Offer
Registration Statement with respect to the Registered Exchange Offer. The
Company shall cause the Exchange Offer Registration Statement to become
effective under the Act within 180 days of the date of the original issuance of
the Securities (or if such 180th day is not a Business Day, the next succeeding
Business Day, such day being an "Effectiveness Deadline"). To the extent not
prohibited by any applicable law or applicable interpretation of the Staff of
the Commission, the Company shall use its best efforts to consummate the
Registered Exchange Offer within 210 days of the date of the original issuance
of the Securities (or if such 210th day is not a Business Day, the next
succeeding Business Day, such day being the "Consummation Deadline").

                  (b)      Upon the effectiveness of the Exchange Offer
Registration Statement, the Company shall promptly commence the Registered
Exchange Offer, it being the objective of such Registered Exchange Offer to
enable each Holder electing to exchange Securities for New Securities (assuming
that such Holder is not an Affiliate of the Company, acquires the New Securities
in the ordinary course of such Holder's business, has no arrangements or
understandings with any Person to participate in the distribution of the New
Securities and is not prohibited by any law or policy of the Commission from
participating in the Registered Exchange Offer) to trade such New Securities
from and after their receipt without any limitations or restrictions under the
Act and without material restrictions under the securities laws of a substantial
proportion of the several states of the United States.

                  (c)      In connection with the Registered Exchange Offer, the
Company shall:

                  (i)      mail 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;

                  (ii)     keep the Registered Exchange Offer open for not less
                  than 20 Business Days and not more than 30 Business Days after
                  the date notice thereof is mailed to the Holders (or, in each
                  case, longer if required by applicable law);

                  (iii)    use its best efforts to keep the Exchange Offer
                  Registration Statement continuously effective under the Act,
                  supplemented and amended as required, under the Act to ensure
                  that it is available for sales of New Securities by Exchanging
                  Dealers during the Exchange Offer Registration Period;

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                  (iv)     utilize the services of a depositary for the
                  Registered Exchange Offer with an address in the Borough of
                  Manhattan, The City of New York, which may be the Trustee or
                  an Affiliate of the Trustee;

                  (v)      permit Holders to withdraw tendered Securities at any
                  time prior to the close of business, New York time, on the
                  last Business Day on which the Registered Exchange Offer is
                  open;

                  (vi)     prior to effectiveness of the Exchange Offer
                  Registration Statement, provide a supplemental letter to the
                  Commission (A) stating that the Company is conducting the
                  Registered Exchange Offer in reliance on the position of the
                  Commission in Exxon Capital Holdings Corporation (pub. avail.
                  May 13, 1988) and Morgan Stanley and Co., Inc. (pub. avail.
                  June 5, 1991); and (B) including a representation that the
                  Company has not entered into any arrangement or understanding
                  with any Person to distribute the New Securities to be
                  received in the Registered Exchange Offer and that, to the
                  best of the Company's information and belief, each Holder
                  participating in the Registered Exchange Offer is acquiring
                  the New Securities in the ordinary course of business and has
                  no arrangement or understanding with any Person to participate
                  in the distribution of the New Securities; and

                  (vii)    comply in all respects with all applicable laws.

                  (d)      As soon as practicable after the close of the
Registered Exchange Offer, the Company shall:

                  (i)      accept for exchange all Securities tendered and not
                  validly withdrawn pursuant to the Registered Exchange Offer in
                  accordance with the terms of the Exchange Offer Registration
                  Statement;

                  (ii)     deliver to the Trustee for cancellation in accordance
                  with Section 4(s) all Securities so accepted for exchange; and

                  (iii)    cause the Trustee promptly to authenticate and
                  deliver to each Holder of Securities a principal amount of New
                  Securities equal to the principal amount of the Securities of
                  such Holder so accepted for exchange.

                  (e)      Each Holder, by its purchase and acceptance of the
Securities held by it, shall be deemed to have acknowledged and agreed that any
Broker-Dealer and any Holder using the Registered Exchange Offer to participate
in a distribution of the New Securities (x) could not under Commission policy as
in effect on the date of this Agreement rely on the position of the Commission
in Morgan Stanley and Co., Inc. (pub. avail. June 5, 1991) and Exxon Capital
Holdings Corporation (pub. avail. May 13, 1988), as interpreted in the
Commission's letter to Shearman & Sterling dated July 2, 1993, and similar
no-action letters; and (y) must comply with the registration and prospectus
delivery requirements of the Act in connection with any secondary resale
transaction and that such a secondary resale transaction must be covered by an
effective registration statement containing the selling security holder
information required by

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Item 507 or 508, as applicable, of Regulation S-K under the Act if the resales
are of New Securities obtained by such Holder in exchange for Securities
acquired by such Holder directly from the Company or one of its Affiliates.
Accordingly, each Holder participating in the Registered Exchange Offer shall be
required to represent to the Company that, at the time of the consummation of
the Registered Exchange Offer:

                  (i)      any New Securities received by such Holder will be
                  acquired in the ordinary course of business;

                  (ii)     such Holder will have no arrangement or understanding
                  with any Person to participate in the distribution of the
                  Securities or the New Securities within the meaning of the
                  Act; and

                  (iii)    such Holder is not an Affiliate of the Company.

                  (f)      If any Initial Purchaser determines that it is not
eligible to participate in the Registered Exchange Offer with respect to the
exchange of Securities constituting any portion of an unsold allotment, at the
request of such Initial Purchaser, the Company shall issue and deliver to such
Initial Purchaser or the Person purchasing New Securities registered under a
Shelf Registration Statement as contemplated by Section 3 hereof from such
Initial Purchaser, in exchange for such Securities, a like principal amount of
New Securities. The Company shall use its best efforts to cause the CUSIP
Service Bureau to issue the same CUSIP number for such New Securities as for New
Securities issued pursuant to the Registered Exchange Offer.

         3.       Shelf Registration.

                  (a)      If (i) due to any change in law or applicable
interpretations thereof by the Commission's staff, the Company determines upon
advice of its outside counsel that it is not permitted to effect the Registered
Exchange Offer as contemplated by Section 2 hereof; or

                  (ii)     for any other reason the Registered Exchange Offer is
                  not consummated within 210 days of the date hereof;

                  (iii)    any Initial Purchaser so requests with respect to
                  Securities that are not eligible to be exchanged for New
                  Securities in the Registered Exchange Offer and that are held
                  by it following consummation of the Registered Exchange Offer;

                  (iv)     any Holder (other than an Initial Purchaser) is not
                  eligible to participate in the Registered Exchange Offer; or

                  (v)      in the case of any Initial Purchaser that
                  participates in the Registered Exchange Offer or acquires New
                  Securities pursuant to Section 2(f) hereof, such Initial
                  Purchaser does not receive freely tradeable New Securities in
                  exchange for Securities constituting any portion of an unsold
                  allotment (it being understood that (x) the requirement that
                  an Initial Purchaser deliver a Prospectus containing the
                  information required by Item 507 or 508 of Regulation S-K
                  under the Act in connection with sales of New Securities
                  acquired in exchange for such Securities

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                  shall result in such New Securities being not "freely
                  tradeable"; and (y) the requirement that an Exchanging Dealer
                  deliver a Prospectus in connection with sales of New
                  Securities acquired in the Registered Exchange Offer in
                  exchange for Securities acquired as a result of market-making
                  activities or other trading activities shall not result in
                  such New Securities being not "freely tradeable"), the Company
                  shall effect a Shelf Registration Statement in accordance with
                  subsection (b) below.

                  (b)      (i)      To the extent not prohibited by any
applicable law or applicable interpretation of the Staff of the Commission, the
Company shall as promptly as practicable (but in no event more than 90 days
after so required or requested pursuant to this Section 3, such day being a
"Filing Deadline"), file with the Commission and thereafter shall use its best
efforts to cause to be declared effective under the Act within 180 days after so
requested or required pursuant to this Section 3 (such day being an
"Effectiveness Deadline") a Shelf Registration Statement relating to the offer
and sale of the Securities or the New Securities, as applicable, by the Holders
thereof from time to time in accordance with the methods of distribution elected
by such Holders and set forth in such Shelf Registration Statement; provided,
however, that no Holder (other than an Initial Purchaser) shall be entitled to
have the Securities held by it covered by such Shelf Registration Statement
unless such Holder agrees in writing to be bound by all of the provisions of
this Agreement applicable to such Holder; and provided further, that with
respect to New Securities received by an Initial Purchaser in exchange for
Securities constituting any portion of an unsold allotment, the Company may, if
permitted by current interpretations by the Commission's staff, file a
post-effective amendment to the Exchange Offer Registration Statement containing
the information required by Item 507 or 508 of Regulation S-K, as applicable, in
satisfaction of its obligations under this subsection with respect thereto, and
any such Exchange Offer Registration Statement, as so amended, shall be referred
to herein as, and governed by the provisions herein applicable to, a Shelf
Registration Statement.

                           (ii)     The Company shall use its best efforts to
                  keep the Shelf Registration Statement continuously effective,
                  supplemented and amended as required by the Act, in order to
                  permit the Prospectus forming part thereof to be usable by
                  Holders for a period of two years (or such shorter period as
                  may hereafter be provided in Rule 144(k) under the Securities
                  Act) from the date of the original issuance of the Securities
                  or such shorter period that will terminate when all the
                  Securities or New Securities, as applicable, covered by the
                  Shelf Registration Statement have been sold pursuant to the
                  Shelf Registration Statement (in any such case, such period
                  being called the "Shelf Registration Period"). The Company
                  shall be deemed not to have used its best efforts to keep the
                  Shelf Registration Statement effective during the requisite
                  period if it voluntarily takes any action that would result in
                  Holders of Securities covered thereby not being able to offer
                  and sell such Securities during that period, unless (A) such
                  action is required by applicable law, or (B) such action is
                  taken by the Company in good faith and for valid business
                  reasons (not including avoidance of the Company's obligations
                  hereunder), including the acquisition or divestiture of
                  assets, so long as the Company promptly thereafter complies
                  with the requirements of Section 4(k) hereof, if applicable.

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                           (iii)    The Company shall cause the Shelf
                  Registration Statement and the related Prospectus and any
                  amendment or supplement thereto, as of the effective date of
                  the Shelf Registration Statement or such amendment or
                  supplement, (A) to comply in all material respects with the
                  applicable requirements of the Securities Act and the rules
                  and regulations of the Commission; and (B) not to contain any
                  untrue statement of a material fact or omit to state a
                  material fact required to be stated therein or necessary in
                  order to make the statements therein, in the light of the
                  circumstances under which they were made, not misleading.

         4.       Additional Registration Procedures. In connection with any
Shelf Registration Statement and, to the extent applicable, any Exchange Offer
Registration Statement, the following provisions shall apply.

                  (a)      The Company shall:

                  (i)      furnish to you, not less than five Business Days
                  prior to the filing thereof with the Commission, a copy of any
                  Exchange Offer Registration Statement and any Shelf
                  Registration Statement, and each amendment thereof and each
                  amendment or supplement, if any, to the Prospectus included
                  therein and shall use its best efforts to reflect in each such
                  document, when so filed with the Commission, such comments as
                  you reasonably propose;

                  (ii)     include the information set forth in Annex A hereto
                  on the facing page of the Exchange Offer Registration
                  Statement, in Annex B hereto in the forepart of the Exchange
                  Offer Registration Statement in a section setting forth
                  details of the Exchange Offer, in Annex C hereto in the
                  underwriting or plan of distribution section of the Prospectus
                  contained in the Exchange Offer Registration Statement, and in
                  Annex D hereto in the letter of transmittal delivered pursuant
                  to the Registered Exchange Offer;

                  (iii)    if requested by an Initial Purchaser, include the
                  information required by Item 507 or 508 of Regulation S-K, as
                  applicable, in the Prospectus contained in the Exchange Offer
                  Registration Statement; and

                  (iv)     in the case of a Shelf Registration Statement,
                  include the names of the Holders that propose to sell
                  Securities pursuant to the Shelf Registration Statement as
                  selling security holders.

                  (b)      The Company shall ensure that:

                  (i)      any Registration Statement and any amendment thereto
                  and any Prospectus forming part thereof and any amendment or
                  supplement thereto complies in all material respects with the
                  Act and the rules and regulations thereunder; and

                  (ii)     any 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

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                  material fact required to be stated therein or necessary to
                  make the statements therein not misleading.

                  (c)      The Company shall promptly give written notice to
you, the Holders of Securities covered by any Shelf Registration Statement and
any Exchanging Dealer under any Exchange Offer Registration Statement that has
provided in writing to the Company a telephone or facsimile number and address
for notices, and, if requested by you or any such Holder or Exchanging Dealer,
shall confirm such advice in writing (which notice pursuant to clauses (ii)-(v)
hereof shall be accompanied by an instruction to suspend the use of the
Prospectus until the Company shall have remedied the basis for such suspension):

                  (i)      when a Registration Statement and any amendment
                  thereto has been filed with the Commission and when the
                  Registration Statement or any post-effective amendment thereto
                  has become effective;

                  (ii)     of any request by the Commission for any amendment or
                  supplement to the Registration Statement or the Prospectus
                  included therein or for additional information;

                  (iii)    of the issuance by the Commission of any stop order
                  suspending the effectiveness of the Registration Statement or
                  the initiation of any proceedings for that purpose;

                  (iv)     of the receipt by the Company or its legal counsel of
                  any notification with respect to the suspension of the
                  qualification of the securities included therein for sale in
                  any jurisdiction or the initiation of any proceeding for such
                  purpose; and

                  (v)      of the happening of any event that requires any
                  change in the Registration Statement or the Prospectus
                  included therein so that, as of such date, the Registration
                  Statement or the Prospectus do not contain an untrue statement
                  of a material fact nor omit to state a material fact required
                  to be stated therein or necessary to make the statements
                  therein (in the case of the Prospectus, in the light of the
                  circumstances under which they were made) not misleading.

                  (d)      The Company shall use its best efforts to obtain the
withdrawal of any order suspending the effectiveness of any Registration
Statement or the qualification of the securities therein for sale in any
jurisdiction at the earliest possible time.

                  (e)      The Company shall furnish to each Holder of
Securities covered by any Shelf Registration Statement, without charge, at least
one copy of such Shelf Registration Statement and any post-effective amendment
thereto, including all periodic reports incorporated therein by reference, and,
if the Holder so requests in writing, all exhibits thereto (including exhibits
incorporated by reference therein).

                  (f)      The Company shall, during the Shelf Registration
Period, deliver to each Holder of Securities covered by any Shelf Registration
Statement, without charge, as many copies of the Prospectus (including each
preliminary Prospectus) included in such Shelf

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Registration Statement and any amendment or supplement thereto as such Holder
may reasonably request. The Company consents to the use of the Prospectus or any
amendment or supplement thereto by each of the selling Holders of securities in
connection with the offering and sale of the securities covered by the
Prospectus, or any amendment or supplement thereto, included in the Shelf
Registration Statement.

                  (g)      The Company shall furnish to each Exchanging Dealer
which so requests, without charge, at least one copy of the Exchange Offer
Registration Statement and any post-effective amendment thereto, including all
periodic reports incorporated by reference therein, and, if the Exchanging
Dealer so requests in writing, all exhibits thereto (including exhibits
incorporated by reference therein).

                  (h)      The Company shall promptly deliver to each Initial
Purchaser, each Exchanging Dealer and each other Person required to deliver a
Prospectus during the Exchange Offer Registration Period, without charge, as
many copies of the Prospectus included in such Exchange Offer Registration
Statement and any amendment or supplement thereto as any such Person may
reasonably request. The Company consents to the use of the Prospectus or any
amendment or supplement thereto by any Initial Purchaser, any Exchanging Dealer
and any such other Person that may be required to deliver a Prospectus following
the Registered Exchange Offer in connection with the offering and sale of the
New Securities covered by the Prospectus, or any amendment or supplement
thereto, included in the Exchange Offer Registration Statement.

                  (i)      Prior to the Registered Exchange Offer or any other
offering of Securities pursuant to any Registration Statement, the Company shall
arrange, if necessary, for the qualification of the Securities or the New
Securities for sale under the laws of such jurisdictions as any Holder shall
reasonably request and will maintain such qualification in effect so long as
required; provided that in no event shall the Company be obligated to qualify to
do business in any jurisdiction where it is not then so qualified or to take any
action that would subject it to service of process in suits, other than those
arising out of the Initial Placement, the Registered Exchange Offer or any
offering pursuant to a Shelf Registration Statement, in any such jurisdiction
where it is not then so subject.

                  (j)      The Company shall cooperate with the Holders of
Securities to facilitate the timely preparation and delivery of certificates
representing New Securities or Securities to be issued or sold pursuant to any
Registration Statement free of any restrictive legends and in such denominations
and registered in such names as Holders may request.

                  (k)      Upon the occurrence of any event contemplated by
subsections (c)(ii) through (v) above, the Company shall promptly prepare and
file a post-effective amendment to the applicable Registration Statement or an
amendment or supplement to the related Prospectus or file any other required
document so that, as thereafter delivered to the Holders of the Securities
included therein or purchasers of Securities, the Prospectus will not contain an
untrue statement of a material fact or omit to state any material fact necessary
to make the statements therein, in the light of the circumstances under which
they were made, not misleading. In such circumstances, the period of
effectiveness of the Exchange Offer Registration Statement

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provided for in Section 2 and the Shelf Registration Statement provided for in
Section 3(b) shall each be extended by the number of days from and including the
date of the giving of a notice of suspension pursuant to Section 4(d) to and
including the date when the Initial Purchasers, the Holders of the Securities
and any known Exchanging Dealer shall have received such amended or supplemented
Prospectus pursuant to this Section.

                  (l)      Not later than the effective date of any Registration
Statement, the Company shall provide a CUSIP number for the Securities or the
New Securities, as the case may be, registered under such Registration Statement
and provide the Trustee with printed certificates for such Securities or New
Securities, in a form eligible for deposit with The Depository Trust Company.

                  (m)      The Company will comply with all applicable rules and
regulations of the Commission and make generally available to its security
holders as soon as practicable after the effective date of the applicable
Registration Statement an earnings statement satisfying the provisions of
Section 11(a) of the Act; provided that, in no event shall such earnings
statement be delivered later than 45 days after the end of a 12-month period (or
90 days if such period is a fiscal year) beginning with the first month of the
Company's first fiscal quarter commencing after the effective date of the
Registration Statement, which statement shall cover such 12-month period.

                  (n)      The Company shall cause the Indenture to be qualified
under the Trust Indenture Act in a timely manner.

                  (o)      The Company may require each Holder of Securities to
be sold pursuant to any Shelf Registration Statement to furnish to the Company
such information regarding the Holder and the distribution of such Securities as
the Company may from time to time reasonably require for inclusion in such
Registration Statement. The Company may exclude from such Shelf Registration
Statement the Securities of any Holder that unreasonably fails to furnish such
information within a reasonable time after receiving such request.

                  (p)      In the case of any Shelf Registration Statement, the
Company shall enter into such customary agreements (including if requested an
underwriting agreement in customary form) and take all other appropriate actions
in order to expedite or facilitate the registration or the disposition of the
Securities, and in connection therewith, if an underwriting agreement is entered
into, cause the same to contain indemnification provisions and procedures no
less favorable than those set forth in Section 6 (or such other provisions and
procedures acceptable to the Majority Holders and the Managing Underwriters, if
any, with respect to all parties to be indemnified pursuant to Section 6.

                  (q)      In the case of any Shelf Registration Statement, the
Company shall, if requested by (A) and Initial Purchaser in the case where such
Initial Purchaser holds Securities acquired in the Initial Placement or (B)
Holders of at least 25% in aggregate principal amount of the Securities:

                  (i)      make reasonably available for inspection by the
                  Holders of Securities to be registered thereunder, any
                  underwriter participating in any disposition pursuant

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                  to such Registration Statement, and any attorney, accountant
                  or other agent retained by the Holders or any such underwriter
                  all relevant financial and other records, pertinent corporate
                  documents and properties of the Company and its subsidiaries;

                  (ii)     cause the Company's officers, directors and employees
                  to supply all relevant information reasonably requested by the
                  Holders or any such underwriter, attorney, accountant or agent
                  in connection with any such Registration Statement as is
                  customary for similar due diligence examinations; provided,
                  however, that any information that is designated in writing by
                  the Company, in good faith, as confidential at the time of
                  delivery of such information shall be kept confidential by the
                  Holders or any such underwriter, attorney, accountant or
                  agent, unless such disclosure is made in connection with a
                  court proceeding or required by law, or such information
                  becomes available to the public generally or through a third
                  party without an accompanying obligation of confidentiality;

                  (iii)    make such representations and warranties to the
                  Holders of Securities registered thereunder and the
                  underwriters, if any, in form, substance and scope as are
                  customarily made by issuers to underwriters in underwritten
                  offerings and covering matters including, but not limited to,
                  those set forth in the Purchase Agreement;

                  (iv)     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) addressed to each selling Holder and the
                  underwriters, if any, covering such matters as are customarily
                  covered in opinions requested in underwritten offerings and
                  such other matters as may be reasonably requested by such
                  Holders and underwriters;

                  (v)      obtain "cold comfort" letters and updates thereof
                  from the independent certified public accountants of the
                  Company (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 and financial data are, or are required to be,
                  included in the Registration Statement), addressed to each
                  selling Holder of Securities registered thereunder and the
                  underwriters, if any, in customary form and covering matters
                  of the type customarily covered in "cold comfort" letters in
                  connection with primary underwritten offerings; and

                  (vi)     deliver such documents and certificates as may be
                  reasonably requested by the Majority Holders and the Managing
                  Underwriters, if any, including those to evidence compliance
                  with any customary conditions contained in the underwriting
                  agreement or other agreement entered into by the Company.

                  The actions set forth in clauses (iii), (iv), (v) and (vi) of
this Section shall be

                                     - 12 -

<PAGE>

performed at (A) the effectiveness of such Registration Statement and each
post-effective amendment thereto; and (B) each closing under any underwriting or
similar agreement as and to the extent required thereunder.

                  (r)      In the case of any Exchange Offer Registration
Statement, the Company shall:

                  (i)      make reasonably available for inspection by such
                  Initial Purchaser, and any attorney, accountant or other agent
                  retained by such Initial Purchaser, all relevant financial and
                  other records, pertinent corporate documents and properties of
                  the Company and its subsidiaries;

                  (ii)     cause the Company's officers, directors and employees
                  to supply all relevant information reasonably requested by
                  such Initial Purchaser or any such attorney, accountant or
                  agent in connection with any such Registration Statement as is
                  customary for similar due diligence examinations; provided,
                  however, that any information that is designated in writing by
                  the Company, in good faith, as confidential at the time of
                  delivery of such information shall be kept confidential by
                  such Initial Purchaser or any such attorney, accountant or
                  agent, unless such disclosure is made in connection with a
                  court proceeding or required by law, or such information
                  becomes available to the public generally or through a third
                  party without an accompanying obligation of confidentiality;

                  (iii)    make such representations and warranties to such
                  Initial Purchaser, in form, substance and scope as are
                  customarily made by issuers to underwriters in primary
                  underwritten offerings and covering matters including, but not
                  limited to, those set forth in the Purchase Agreement;

                  (iv)     obtain opinions of counsel to the Company and updates
                  thereof (which counsel and opinions (in form, scope and
                  substance) shall be reasonably satisfactory to such Initial
                  Purchaser and its counsel, addressed to such Initial
                  Purchaser, covering such matters as are customarily covered in
                  opinions requested in underwritten offerings and such other
                  matters as may be reasonably requested by such Initial
                  Purchaser or its counsel;

                  (v)      obtain "cold comfort" letters and updates thereof
                  from the independent certified public accountants of the
                  Company (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 and financial data are, or are required to be,
                  included in the Registration Statement), addressed to such
                  Initial Purchaser, in customary form and covering matters of
                  the type customarily covered in "cold comfort" letters in
                  connection with primary underwritten offerings, or if
                  requested by such Initial Purchaser or its counsel in lieu of
                  a "cold comfort" letter, an agreed-upon procedures letter
                  under Statement on Auditing Standards No. 35, covering matters
                  requested by such Initial Purchaser or its counsel; and

                                     - 13 -

<PAGE>

                  (vi)     deliver such documents and certificates as may be
                  reasonably requested by such Initial Purchaser or its counsel,
                  including those to evidence compliance with Section 4(k) and
                  with conditions customarily contained in underwriting
                  agreements.

                  The foregoing actions set forth in clauses (iii), (iv), (v),
and (vi) of this Section shall be performed at the close of the Registered
Exchange Offer and the effective date of any post-effective amendment to the
Exchange Offer Registration Statement.

                  (s)      If a Registered Exchange Offer is to be consummated,
upon delivery of the Securities by Holders to the Company (or to such other
Person as directed by the Company) in exchange for the New Securities, the
Company shall mark, or caused to be marked, on the Securities so exchanged that
such Securities are being canceled in exchange for the New Securities. In no
event shall the Securities be marked as paid or otherwise satisfied.

                  (t)      The Company will use its best efforts (i) if the
Securities have been rated prior to the initial sale of such Securities pursuant
to the Purchase Agreement, to confirm such ratings will apply to the Securities
or the New Securities, as the case may be, covered by a Registration Statement;
or (ii) if the Securities were not previously rated, to cause the Securities
covered by a Registration Statement to be rated with at least one nationally
recognized statistical rating agency, if so requested by Majority Holders with
respect to the related Registration Statement or by any Managing Underwriters.

                  (u)      In the event that any Broker-Dealer shall underwrite
any Securities or participate as a member of an underwriting syndicate or
selling group or "assist in the distribution" (within the meaning of the Rules
of Fair Practice and the By-Laws of the National Association of Securities
Dealers, Inc.) thereof, whether as a Holder of such Securities or as an
underwriter, a placement or sales agent or a broker or dealer in respect
thereof, or otherwise, assist such Broker-Dealer in complying with the
requirements of such Rules and By-Laws, including, without limitation, by:

                  (i)      if such Rules or By-Laws shall so require, engaging a
                  "qualified independent underwriter" (as defined in such Rules)
                  to participate in the preparation of the Registration
                  Statement, to exercise usual standards of due diligence with
                  respect thereto and, if any portion of the offering
                  contemplated by such Registration Statement is an underwritten
                  offering or is made through a placement or sales agent, to
                  recommend the yield of such Securities;

                  (ii)     indemnifying any such qualified independent
                  underwriter to the extent of the indemnification of
                  underwriters provided in Section 6 hereof; and

                  (iii)    providing such information to such Broker-Dealer as
                  may be required in order for such Broker-Dealer to comply with
                  the requirements of such Rules.

                  (v)      The Company shall use its best efforts to take all
other steps necessary to effect the registration of the Securities or the New
Securities, as the case may be, covered by a Registration Statement.

                                     - 14 -

<PAGE>

         5.       Registration Expenses. The Company shall bear all expenses
incurred in connection with the performance of its obligations hereunder and, in
the event of any Shelf Registration Statement, will reimburse the Holders for
the reasonable fees and disbursements of one firm or counsel designated by the
Majority Holders to act as counsel for the Holders in connection therewith, and,
in the case of any Exchange Offer Registration Statement, will reimburse the
Initial Purchasers for the reasonable fees and disbursements of their counsel
incurred in connection with their review of the Exchange Offer Registration
Statement.

         6.       Indemnification and Contribution.

                  (a)      The Company agrees to indemnify and hold harmless
each Holder of Securities or New Securities, as the case may be, covered by any
Registration Statement (including each Initial Purchaser and, with respect to
any Prospectus delivery as contemplated in Section 4(h) hereof, each Exchanging
Dealer), the directors, officers, employees and agents of each such Holder and
each Person who controls any such Holder within the meaning of either the Act or
the Exchange Act against any and all losses, claims, damages or liabilities,
joint or several, to which they or any of them may become subject under the Act,
the Exchange Act or other Federal or state statutory law or regulation, at
common law or otherwise, insofar as such losses, claims, damages or liabilities
(or actions in respect thereof) arise out of or are based upon any untrue
statement or alleged untrue statement of a material fact contained in the
Registration Statement as originally filed or in any amendment thereof, or in
any preliminary Prospectus or the Prospectus, or in any amendment thereof or
supplement thereto, or arise out of or are based upon the omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, and agrees to reimburse
each such indemnified party, as incurred, for any legal or other expenses
reasonably incurred by them in connection with investigating or defending any
such loss, claim, damage, liability or action; provided, however, that the
Company will not be liable in any case to the extent that any such loss, claim,
damage or liability arises out of or is based upon any such untrue statement or
alleged untrue statement or omission or alleged omission made therein in
reliance upon and in conformity with written information furnished to the
Company by or on behalf of any such Holder specifically for inclusion therein;
provided, further, that the foregoing indemnity with respect to any untrue
statement contained in or omission from any preliminary prospectus shall not
inure to the benefit of any Holder (or any of the directors, officers, employees
and agents of such Holder or any person controlling such Holder) from whom the
person asserting any such loss, claim, damage or liability purchased the
Securities which are the subject thereof if such person did not receive a copy
of the final prospectus (or the final prospectus as then amended or supplemented
if the Company shall have furnished any amendments or supplements thereto) at or
prior to the confirmation of the sale of such Securities to such person in any
case where such delivery is required by the Act and the untrue statement or
omission of a material fact contained in such preliminary prospectus was
corrected in the final prospectus (or the final prospectus as so amended or
supplemented if the Company shall have furnished any amendments or supplements
thereto), and it is finally judicially determined that such delivery was
required to be made under the Act and was not so made. This indemnity agreement
will be in addition to any liability which the Company may otherwise have.

                                     - 15 -

<PAGE>

         The Company also agrees to indemnify or contribute as provided in
Section 6(d) to Losses of each and any person deemed an "underwriter", under the
Act or the rules and regulations thereunder, of Securities or New Securities, as
the case may be, registered under a Shelf Registration Statement, their
directors, officers, employees or agents and each Person who controls such
underwriter on substantially the same basis as that of the indemnification of
the Initial Purchasers and the selling Holders provided in this Section 6(a) and
shall, if requested by any Holder, enter into an underwriting agreement
reflecting such agreement, as provided in Section 4(p) hereof.

                  (b)      Each Holder of securities covered by a Registration
Statement (including each Initial Purchaser and, with respect to any Prospectus
delivery as contemplated in Section 4(h) hereof, each Exchanging Dealer)
severally agrees to indemnify and hold harmless the Company each of its
directors each of its officers who signs such Registration Statement and each
Person who controls the Company within the meaning of either the Act or the
Exchange Act, to the same extent as the foregoing indemnity from the Company to
each such Holder, but only with reference to written information relating to
such Holder furnished to the Company by or on behalf of such Holder specifically
for inclusion in the documents referred to in the foregoing indemnity. This
indemnity agreement will be in addition to any liability which any such Holder
may otherwise have.

                  (c)      Promptly after receipt by an indemnified party under
this Section 6 or notice of the commencement of any action, such indemnified
party will, if a claim in respect thereof is to be made against the indemnifying
party under this Section, notify the indemnifying party in writing of the
commencement thereof; but the failure so to notify the indemnifying party (i)
will not relieve it from liability under paragraph (a) or (b) above unless and
to the extent it did not otherwise learn of such action and such failure results
in the forfeiture by the indemnifying party of substantial rights and defenses;
and (ii) will not, in any event, relieve the indemnifying party from any
obligations to any indemnified party other than the indemnification obligation
provided in paragraph (a) or (b) above. The indemnifying party shall be entitled
to appoint counsel of the indemnifying party's choice at the indemnifying
party's expense to represent the indemnified party in any action for which
indemnification is sought (in which case the indemnifying party shall not
thereafter be responsible for the fees and expenses of any separate counsel
retained by the indemnified party or parties except as set forth below);
provided, however, that such counsel shall be reasonably satisfactory to the
indemnified party. Notwithstanding the indemnifying party's election to appoint
counsel to represent the indemnified party in an action, the indemnified party
shall have the right to employ separate counsel (including local counsel), and
the indemnifying party shall bear the reasonable fees, costs and expenses of
such separate counsel if (i) the use of counsel chosen by the indemnifying party
to represent the indemnified party would present such counsel with a conflict of
interest; (ii) the actual or potential defendants in, or targets of, any such
action include both the indemnified party and the indemnifying party and the
indemnified party shall have reasonably concluded that there may be legal
defenses available to it and/or other indemnified parties which are different
from or additional to those available to the indemnifying party; (iii) the
indemnifying party shall not have employed counsel satisfactory to the
indemnified party to represent the indemnified party within a reasonable time
after notice of the institution of such action; or (iv) the indemnifying party
shall authorize the indemnified party to employ separate

                                     - 16 -

<PAGE>

counsel at the expense of the indemnifying party, it being understood, however,
that in each case the indemnifying party shall not, in connection with any one
such action or separate but substantially similar or related actions in the same
jurisdiction arising out of the same general allegations or circumstances, be
liable for the reasonable fees and expenses of more than one separate firm of
attorneys (in addition to any local counsel) at any time for all such
indemnified parties, which firm shall be designated by the Representatives if
the indemnified parties consist of the Initial Purchasers or their directors,
officers, employees or agents. An indemnifying party will not, without the prior
written consent of the indemnified parties, settle or compromise or consent to
the entry of any judgment with respect to any pending or threatened claim,
action, suit or proceeding in respect of which indemnification or contribution
may be sought hereunder (whether or not the indemnified parties are actual or
potential parties to such claim or action) unless such settlement, compromise or
consent includes an unconditional release of each indemnified party from all
liability arising out of such claim, action, suit or proceeding.

                  (d)      In the event that the indemnity provided in paragraph
(a) or (b) of this Section is for any reason held to be unenforceable by an
indemnified party although applicable in accordance with its terms, then each
applicable indemnifying party shall have a several and not joint obligation to
contribute to the aggregate losses, claims, damages and liabilities (including
legal or other expenses reasonably incurred in connection with investigating or
defending same) (collectively "Losses") to which such indemnified party may be
subject in such proportion as is appropriate to reflect the relative benefits
received by such indemnifying party, on the one hand, and such indemnified
party, on the other hand, from the Initial Placement and the Registration
Statement which resulted in such Losses; provided, however, that in no case
shall any Initial Purchaser or any subsequent Holder of any Security or New
Security be responsible, in the aggregate, for any amount in excess of the
purchase discount or commission applicable to such Security, or in the case of a
New Security, applicable to the Security that was exchangeable into such New
Security, as set forth on the cover page of the Final Memorandum, nor shall any
underwriter be responsible for any amount in excess of the underwriting discount
or commission applicable to the securities purchased by such underwriter under
the Registration Statement which resulted in such Losses. If the allocation
provided by the immediately preceding sentence is unavailable for any reason,
the indemnifying party and the indemnified party shall contribute in such
proportion as is appropriate to reflect not only such relative benefits but also
the relative fault of such indemnifying party, on the one hand, and such
indemnified party, on the other hand, in connection with the statements or
omissions which resulted in such Losses as well as any other relevant equitable
considerations. Benefits received by the Company shall be deemed to be equal to
the sum of (x) the total net proceeds from the Initial Placement (before
deducting expenses) as set forth on the cover page of the Final Memorandum and
(y) the total amount of Additional Interest (as defined in Section 8) which the
Company was not required to pay as a result of registering the securities
covered by the Registration Statement which resulted in such Losses. Benefits
received by the Initial Purchasers shall be deemed to be equal to the total
purchase discounts and commissions as set forth on the cover page of the Final
Memorandum, and benefits received by any other Holders shall be deemed to be
equal to the value of receiving Securities or New Securities, as applicable,
registered under the Act. Benefits received by any underwriter shall be deemed
to be equal to the total underwriting discounts and commissions, as set forth on
the cover page of the Prospectus forming a part of the Registration Statement
which resulted in such Losses. Relative fault shall be determined by reference
to, among other things,

                                     - 17 -

<PAGE>

whether any alleged untrue statement or omission relates to information provided
by the indemnifying party, on the one hand, or by the indemnified party, on the
other hand, the intent of the parties and their relative knowledge, access to
information and opportunity to correct or prevent such untrue statement or
omission. The parties agree that it would not be just and equitable if
contribution were determined by pro rata allocation (even if the Holders were
treated as one entity for such purpose) or any other method of allocation which
does not take account of the equitable considerations referred to above.
Notwithstanding the provisions of this paragraph (d), no Person guilty of
fraudulent misrepresentation (within the meaning of Section 11(f) of the Act)
shall be entitled to contribution from any Person who was not guilty of such
fraudulent misrepresentation. For purposes of this Section, each Person who
controls a Holder within the meaning of either the Act or the Exchange Act and
each director, officer, employee and agent of such Holder shall have the same
rights to contribution as such Holder, and each Person who controls the Company
within the meaning of either the Act or the Exchange Act, each officer of the
Company who shall have signed the Registration Statement and each director of
the Company shall have the same rights to contribution as the Company, subject
in each case to the applicable terms and conditions of this paragraph (d).

                  (e)      The provisions of this Section will remain in full
force and effect, regardless of any investigation made by or on behalf of any
Holder or the Company or any of the officers, directors or controlling Persons
referred to in this Section hereof, and will survive the sale by a Holder of
securities covered by a Registration Statement.

         7.       Underwritten Registrations.

                  (a)      If any of the Securities or New Securities, as the
case may be, covered by any Shelf Registration Statement are to be sold in an
underwritten offering, the Managing Underwriters shall be selected by the
Majority Holders.

                  (b)      No Person may participate in any underwritten
offering pursuant to any Shelf Registration Statement, unless such Person (i)
agrees to sell such Person's Securities or New Securities, as the case may be,
on the basis reasonably provided in any underwriting arrangements approved by
the Persons entitled hereunder to approve such arrangements; and (ii) completes
and executes all questionnaires, powers of attorney, indemnities, underwriting
agreements and other documents reasonably required under the terms of such
underwriting arrangements.

         8.       Liquidated Damages.

                  (a)      If any of the following events occur (each such event
in clauses (i) through (iv) below being herein called a "Registration Default"):

                  (i)      any Registration Statement required by this Agreement
                  is not filed with the Commission on or prior to the applicable
                  Filing Deadline;

                  (ii)     any Registration Statement required by this Agreement
                  is not declared effective by the Commission on or prior to the
                  applicable Effectiveness Deadline;

                                     - 18 -

<PAGE>

                  (iii)    the Registration Exchange Offer has not been
                  consummated on or prior to the Consummation Deadline; or

                  (iv)     any Registration Statement required by this Agreement
                  has been declared effective by the Commission but (A) such
                  Registration Statement thereafter ceases to be effective,
                  without being succeeded within 45 days by an additional
                  Registration Statement filed and declared effective or (B)
                  such Registration Statement or the related Prospectus ceases
                  to be usable for a period of more than 45 days in connection
                  with resales of Securities during the periods specified herein
                  because either (1) any event occurs as a result of which the
                  related Prospectus forming part of such Registration Statement
                  would include any untrue statement of a material fact or omit
                  to state any material fact necessary to make the statements
                  therein in the light of the circumstances under which they
                  were made not misleading, or (2) it shall be necessary to
                  amend such Registration Statement or supplement the related
                  Prospectus, to comply with the Act or the Exchange Act.

then, as liquidated damages for such Registration default, subject to the
provisions of Section 10, liquidated damages ("Liquidated Damages"), in addition
to the interest set forth in the title of the Securities, will incur from and
including the date on which any such Registration Default shall occur to and
including the first week in which all such Registration Defaults have been
cured, in an amount equal to $0.10 per week per $1,000 principal amount of
outstanding Securities. In no event shall the Liquidated Damages exceed $0.10
per week per $1,000 principal amount of outstanding Securities.

         Notwithstanding anything to the contrary in this Section, the Company
shall not be required to pay Liquidated Damages to a Holder if such Holder
failed to comply with its obligations to make the representations set forth in
Section 2(e) or failed to provide the information required to be provided by it,
if any, pursuant to Section 4(o).

         (b)      A Registration Default referred to in Section 8(a)(iv) hereof
shall be deemed not to have occurred and be continuing in relation to a Shelf
Registration Statement or the related prospectus if (i) such Registration
Default has occurred solely as a result of (x) the filing of a post-effective
amendment to such Shelf Registration Statement to incorporate annual audited
financial information with respect to the Company where such post-effective
amendment is not yet effective and needs to be declared effective to permit
Holders to use the related prospectus or (y) other material events, with respect
to the Company that would need to be described in such Shelf Registration
Statement or the related prospectus (which could include description in a report
filed under the Exchange Act and incorporated by reference in such Shelf
Registration Statement) and (ii) in the case of clause (y), the Company is
proceeding promptly and in good faith to amend or supplement such Shelf
Registration Statement and/or related prospectus to describe such events;
provided, however, that in any case if such Registration Default occurs for a
continuous period in excess of 45 days, Additional Interest shall be payable in
accordance with the above paragraph from the day such Registration Default
occurs until such Registration Default is cured.

                                     - 19 -

<PAGE>

         9.       Rules 144 and 144A. The Company shall use its reasonable best
efforts to file the reports required to be filed by it under the Act and the
Exchange Act in a timely manner and, if at any time the Company is not required
to file such reports, it will, upon the written request of any Holder of
Securities, make publicly available other information so long as necessary to
permit sales of such Holder's Securities pursuant to Rules 144 and 144A under
the Act. The Company covenants that it will take such further action as any
Holder of Securities may reasonably request, all to the extent required from
time to time to enable such Holder to sell Securities without registration under
the Act within the limitation of the exemptions provided by Rules 144 and 144A
(including the requirements of Rule 144A(d)(4)). Upon the written request of any
Holder of Securities, the Company shall deliver to such Holder a written
statement as to whether it has complied with such requirements. The Company will
provide a copy of this Agreement to prospective purchasers of Securities
identified to the Company by the Initial Purchasers upon request.
Notwithstanding the foregoing, nothing in this Section 8 shall be deemed to
require the Company to register any of its securities pursuant to the Exchange
Act.

         10.      Remedies. The Company acknowledges and agrees that any failure
by the Company to comply with its obligations hereunder may result in material
irreparable injury to the Initial Purchasers or the Holders for which there is
no adequate remedy at law, that it will 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 hereunder. The Company further
agrees to waive the defense in any action for specific performance that a remedy
at law would be adequate.

         11.      No Inconsistent Agreements. The Company has not, as of the
date hereof, entered into, nor shall it, on or after the date hereof, enter
into, any agreement with respect to its securities that is inconsistent with the
rights granted to the Holders herein or otherwise conflicts with the provisions
hereof.

         12.      Amendments and Waivers. The provisions of this Agreement,
including the provisions of this sentence, may not be amended, qualified,
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 the Majority Holders (or, after the consummation of any Registered
Exchange Offer in accordance with Section 2 hereof, the Holders of a majority of
the aggregate principal amount of New Securities); provided that, with respect
to any matter that directly or indirectly affects the rights of any Initial
Purchaser hereunder, the Company shall obtain the written consent of each such
Initial Purchaser against which such amendment, qualification, supplement,
waiver or consent is to be effective. Notwithstanding the foregoing (except the
foregoing proviso), a waiver or consent to departure from the provisions hereof
with respect to a matter that relates exclusively to the rights of Holders whose
Securities or New Securities, as the case may be, are being sold pursuant to a
Registration Statement and that does not directly or indirectly affect the
rights of other Holders may be given by the Majority Holders, determined on the
basis of Securities or New Securities, as the case may be, being sold rather
than registered under such Registration Statement.

                                     - 20 -

<PAGE>

         13.      Notices. All notices and other communications provided for or
permitted hereunder shall be made in writing by hand-delivery, first-class mail,
telex, telecopier or air courier guaranteeing overnight delivery:

                  (a)      if to a Holder, at the most current address given by
such holder to the Company, with a copy in like manner to Banc One Capital
Markets, Inc. and UBS Warburg LLC;

                  (b)      if to you, initially at the respective addresses set
forth in the Purchase Agreement; and

                  (c)      if to the Company, initially at its address set forth
in the Purchase Agreement.

         All such notices and communications shall be deemed to have been duly
given when received.

         The Initial Purchasers or the Company by notice to the other parties
may designate additional or different addresses for subsequent notices or
communications.

         14.      Successors. This Agreement shall inure to the benefit of and
be binding upon the successors and assigns of each of the parties, including,
without the need for an express assignment or any consent by the Company
thereto, subsequent Holders of Securities and the New Securities, provided that
nothing herein shall be deemed to permit any assignment, transfer or other
disposition of securities in violation of the terms of the Purchase Agreement or
the Indenture. The Company hereby agrees to extend the benefits of this
Agreement to any Holder of Securities and the New Securities, and any such
Holder may specifically enforce the provisions of this Agreement as if an
original party hereto.

         15.      Counterparts. This agreement may be in signed counterparts,
each of which shall be deemed to be an original and all of which together shall
constitute one and the same agreement.

         16.      Headings. The headings used herein are for convenience only
and shall not affect the construction hereof.

         17.      Applicable Law. This Agreement shall be governed by and
construed in accordance with the laws of the State of New York applicable to
contracts made and to be performed in the State of New York.

         18.      Severability. In the event that any one of more of the
provisions contained herein, or the application thereof in any circumstances, is
held invalid, illegal or unenforceable in any respect for any reason, the
validity, legality and enforceability of any such provision in every other
respect and of the remaining provisions hereof shall not be in any way impaired
or affected thereby, it being intended that all of the rights and privileges of
the parties shall be enforceable to the fullest extent permitted by law.

                                     - 21 -

<PAGE>

         19.      Securities Held by the Company, etc. Whenever the consent or
approval of Holders of a specified percentage of principal amount of Securities
or New Securities is required hereunder, Securities or New Securities, as
applicable, held by the Company or its Affiliates (other than subsequent Holders
of Securities or New Securities if such subsequent Holders are deemed to be
Affiliates solely by reason of their holdings of such Securities or New
Securities) shall not be counted in determining whether such consent or approval
was given by the Holders of such required percentage.

                             signature page follows

                                     - 22 -

<PAGE>

         If the foregoing is in accordance with your understanding of our
agreement, please sign and return to us the enclosed duplicate hereof, whereupon
this letter and your acceptance shall represent a binding agreement among the
Company and the several Initial Purchasers.

                                                 Very truly yours,

                                                 PUBLIC SERVICE COMPANY
                                                 OF COLORADO

                                                  /S/ BENJAMIN G.S. FOWKE III
                                                 -------------------------------
                                                 Benjamin G.S. Fowke III
                                                 Vice President and Treasurer

The foregoing Agreement is hereby confirmed and
accepted as of the date first above written.

BANC ONE CAPITAL MARKETS, INC.

By:  /S/ WENDY BREUDER
    ---------------------------------------
Name:  Wendy Breuder
Title: Managing Director

UBS WARBURG LLC

By:  /S/ CHRISTOPHER FORSHNER                   By:  /S/ RYAN DONOVAN
    ---------------------------------------         ---------------------------
Name:  Christopher Forshner                     Name:  Ryan Donovan
Title: Executive Director                       Title: Associate Director

For themselves and the other
several Initial Purchasers
named in Schedule I to the
Purchase Agreement.

<PAGE>

                                                                         ANNEX A

         Each Broker-Dealer that receives New Securities for its own account
pursuant to the Exchange Offer must acknowledge that it will deliver a
prospectus in connection with any resale of such New Securities. The Letter of
Transmittal states that by so acknowledging and by delivering a prospectus, a
Broker-Dealer will not be deemed to admit that it is an "underwriter" within the
meaning of the Securities Act. This Prospectus, as it may be amended or
supplemented from time to time, may be used by a Broker-Dealer in connection
with resales of New Securities received in exchange for Securities where such
Securities were acquired by such Broker-Dealer as a result of market-making
activities or other trading activities. The Company has agreed that, starting on
the Expiration Date (as defined herein) and ending on the close of business 210
days after the Expiration Date, it will make this Prospectus available to any
Broker-Dealer for use in connection with any such resale. See "Plan of
Distribution".

<PAGE>

                                                                         ANNEX B

         Each Broker-Dealer that receives New Securities for its own account in
exchange for Securities, where such Securities were acquired by such
Broker-Dealer as a result of market-making activities or other trading
activities, must acknowledge that it will deliver a prospectus in connection
with any resale of such New Securities. See "Plan of Distribution".

<PAGE>

                                                                         ANNEX C

                              PLAN OF DISTRIBUTION

         Each Broker-Dealer that receives New Securities for its own account
pursuant to the Exchange Offer must acknowledge that it will deliver a
prospectus in connection with any resale of such New Securities. This
Prospectus, as it may be amended or supplemented from time to time, may be used
by a Broker-Dealer in connection with resales of New Securities received in
exchange for Securities where such Securities were acquired as a result of
market-making activities or other trading activities. The Company has agreed
that, starting on the Expiration Date and ending on the close of business 210
days after the Expiration Date, it will make this Prospectus, as amended or
supplemented, available to any Broker-Dealer for use in connection with any such
resale. In addition, until __________, 20___, all dealers effecting transactions
in the New Securities may be required to deliver a prospectus.

         The Company will not receive any proceeds from any sale of New
Securities by Broker-Dealers. New Securities received by Broker-Dealers for
their own account pursuant to the Exchange Offer may be sold from time to time
in one or more transactions in the over-the-counter market, in negotiated
transactions, through the writing of options on the New Securities or a
combination of such methods of resale, at market prices prevailing at the time
of resale, at prices related to such prevailing market prices or negotiated
prices. Any such resale may be made directly to purchasers or to or through
brokers or dealers who may receive compensation in the form of commissions or
concessions from any such Broker-Dealer and/or the purchasers of any such New
Securities. Any Broker-Dealer that resells New Securities that were received by
it for its own account pursuant to the Exchange Offer and any broker or dealer
that participates in a distribution of such New Securities may be deemed to be
an "underwriter" within the meaning of the Securities Act and any profit of any
such resale of New Securities and any commissions or concessions received by any
such Persons may be deemed to be underwriting compensation under the Securities
Act. The Letter of Transmittal states that by acknowledging that it will deliver
and by delivering a prospectus, a Broker-Dealer will not be deemed to admit that
it is an "underwriter" within the meaning of the Securities Act.

         For a period commencing on Expiration Date and ending 210 days after
the Expiration Date, the Company will promptly send additional copies of this
Prospectus and any amendment or supplement to this Prospectus to any
Broker-Dealer that requests such documents in the Letter of Transmittal. The
Company has agreed to pay all expenses incident to the Exchange Offer (including
the expenses of one counsel for the holder of the Securities) other than
commissions or concessions of any brokers or dealers and will indemnify the
holders of the Securities (including any Broker-Dealers) against certain
liabilities, including liabilities under the Securities Act.

<PAGE>

                                                                         ANNEX D

Rider A

CHECK HERE IF YOU ARE A BROKER-DEALER AND WISH TO RECEIVE 10 ADDITIONAL COPIES
OF THE PROSPECTUS AND 10 COPIES OF ANY AMENDMENTS OR SUPPLEMENTS THERETO.

Name:       ________________________________________
Address:    ________________________________________
            ________________________________________

Rider B

If the undersigned is not a Broker-Dealer, the undersigned represents that it
acquired the New Securities in the ordinary course of its business, it is not
engaged in, and does not intend to engage in, a distribution of New Securities
and it has not arrangements or understandings with any Person to participate in
a distribution of the New Securities. If the undersigned is a Broker-Dealer that
will receive New Securities for its own account in exchange for Securities, it
represents that the Securities to be exchange for New Securities were acquired
by it as a result of market-making activities or other trading activities and
acknowledges that it will deliver a prospectus in connection with any resale of
such New Securities; however, by so acknowledging and by delivering a
prospectus, the undersigned will not be deemed to admit that it is an
"underwriter" within the meaning of the Securities Act.<PAGE>

                                                                     EXHIBIT 4.4

                             SUPPLEMENTAL INDENTURE

                            (DATED AS OF MAY 1, 2003)

                                  ------------

                       PUBLIC SERVICE COMPANY OF COLORADO

                                       TO

                      U.S. BANK TRUST NATIONAL ASSOCIATION,

                                                        AS TRUSTEE

                                  ------------

                   CREATING AN ISSUE OF FIRST MORTGAGE BONDS,
                               COLLATERAL SERIES M

                                 ---------------

      (SUPPLEMENTAL TO INDENTURE DATED AS OF DECEMBER 1, 1939, AS AMENDED)

<PAGE>

         SUPPLEMENTAL INDENTURE, dated as of May 1, 2003, between PUBLIC SERVICE
         COMPANY OF COLORADO, a corporation organized and existing under the
         laws of the State of Colorado (the "Company"), party of the first part,
         and U.S. BANK TRUST NATIONAL ASSOCIATION (FORMERLY FIRST TRUST OF NEW
         YORK, NATIONAL ASSOCIATION), a national banking association, as
         successor trustee (the "Trustee") to Morgan Guaranty Trust Company of
         New York (formerly Guaranty Trust Company of New York), party of the
         second part.

         WHEREAS, the Company heretofore executed and delivered to the Trustee
         its Indenture, dated as of December 1, 1939 (the "Principal
         Indenture"), to secure its First Mortgage Bonds from time to time
         issued thereunder; and

         WHEREAS, the Company has heretofore executed and delivered to the
         Trustee the Supplemental Indentures referred to in Schedule A hereto
         for certain purposes, including the creation of series of bonds, the
         subjection to the lien of the Principal Indenture of property acquired
         after the execution and delivery thereof, the amendment of certain
         provisions of the Principal Indenture and the appointment of the
         successor Trustee; and

         WHEREAS, the Principal Indenture as supplemented and amended by all
         Supplemental Indentures heretofore executed by the Company and the
         Trustee is hereinafter referred to as the "Indenture", and, unless the
         context requires otherwise, references herein to Articles and Sections
         of the Indenture shall be to Articles and Sections of the Principal
         Indenture as so amended; and

         WHEREAS, the Company proposes to create a new series of First Mortgage
         Bonds to be designated as First Mortgage Bonds, Collateral Series M
         (the "Collateral Series M Bonds"), to be issued and delivered to the
         trustee under the 1993 Mortgage (as hereinafter defined) as the basis
         for the authentication and delivery under the 1993 Mortgage of a series
         of securities, all as hereinafter provided, and to vary in certain
         respects the covenants and provisions contained in Article V of the
         Indenture, to the extent that such covenants and provisions apply to
         the Collateral Series M Bonds; and

         WHEREAS, the Company, pursuant to the provisions of the Indenture, has,
         by appropriate corporate action, duly resolved and determined to
         execute this Supplemental Indenture for the purpose of providing for
         the creation of the Collateral Series M Bonds and of specifying the
         form, provisions and particulars thereof, as in the Indenture provided
         or permitted and of giving to the Collateral Series M Bonds the
         protection and security of the Indenture; and

         WHEREAS, the Company represents that all acts and proceedings required
         by law and by the charter and by-laws of the Company, including all
         action requisite on the part of its shareholders, directors and
         officers, necessary to make the Collateral Series M Bonds, when
         executed by the Company, authenticated and delivered by the Trustee and
         duly issued, the valid, binding and legal obligations of the Company,
         and to constitute the Principal Indenture and all indentures
         supplemental thereto, including this Supplemental Indenture, valid,
         binding and legal instruments for the security of the bonds of all
         series, including the Collateral Series M Bonds, in accordance with the
         terms of such bonds and

<PAGE>

         such instruments, have been done, performed and fulfilled, and the
         execution and delivery hereof have been in all respects duly
         authorized;

         NOW, THEREFORE, THIS SUPPLEMENTAL INDENTURE WITNESSETH:

         That Public Service Company of Colorado, the Company named in the
         Indenture, in consideration of the premises and of One Dollar to it
         duly paid by the Trustee at or before the ensealing and delivery of
         these presents, the receipt whereof is hereby acknowledged, and in
         pursuance of the direction and authority of the Board of Directors of
         the Company given at a meeting thereof duly called and held, and in
         order to create the Collateral Series M Bonds and to specify the form,
         terms and provisions thereof, and to secure the payment of the
         principal of and premium, if any, and interest, if any, on all bonds
         from time to time outstanding under the Indenture, including the
         Collateral Series M Bonds, according to the terms of said bonds, and to
         secure the performance and observance of all of the covenants and
         conditions contained in the Indenture, has executed and delivered this
         Supplemental Indenture and has granted, bargained, sold, warranted,
         aliened, remised, released, conveyed, assigned, transferred, mortgaged,
         pledged, set over and confirmed unto U.S. Bank Trust National
         Association, as Trustee, and its successor or successors in the trust
         and its and their assigns forever;

         TO HAVE AND TO HOLD all and singular the properties, rights, privileges
         and franchises described in the Principal Indenture and in the several
         Supplemental Indentures hereinabove referred to and owned by the
         Company on the date of the execution and delivery hereof (other than
         property of a character expressly excepted from the lien of the
         Indenture as therein set forth) unto the Trustee and its successor or
         successors and assigns forever;

         SUBJECT, HOWEVER, to permitted encumbrances as defined in the
         Indenture;

         IN TRUST, NEVERTHELESS, upon the terms and trusts set forth in the
         Indenture, for the equal and proportionate benefit and security of all
         present and future holders of the bonds and coupons issued and to be
         issued under the Indenture, including the Collateral Series M Bonds,
         without preference, priority or distinction as to lien (except as any
         sinking, amortization, improvement or other fund established in
         accordance with the provisions of the Indenture or any indenture
         supplemental thereto may afford additional security for the bonds of
         any particular series) of any of said bonds over any others thereof by
         reason of series, priority in the time of the issue or negotiation
         thereof, or otherwise howsoever, except as provided in Section 2 of
         Article IV of the Indenture.

                                  ARTICLE ONE

            CREATION AND DESCRIPTION OF THE COLLATERAL SERIES M BONDS

                  SECTION 1. A new series of bonds to be issued under and
secured by the Indenture is hereby created, the bonds of such new series to be
designated First Mortgage Bonds, Collateral Series M. The Collateral Series M
Bonds shall be limited to an aggregate principal amount of Three Hundred Fifty
Million dollars ($350,000,000), excluding any Collateral Series M Bonds which
may be authenticated and exchanged for or in lieu of or in substitution for or
on

                                        2

<PAGE>

transfer of other Collateral Series M Bonds pursuant to any provisions of the
Indenture. The Collateral Series M Bonds shall mature on May 14, 2004. The
Collateral Series M Bonds shall not bear interest.

                  The principal of each Collateral Series M Bond shall be
payable, upon presentation thereof, at the office or agency of the Company in
the city in which the principal corporate trust office of the 1993 Mortgage
Trustee (as hereinafter defined) is located, in any coin or currency of the
United States of America which at the time of payment shall be legal tender for
the payment of public and private debts.

                  The Collateral Series M Bonds shall be issued and delivered by
the Company to U.S. Bank Trust National Association, as successor trustee under
the Indenture, dated as of October 1, 1993, as supplemented (the "1993
Mortgage"), of the Company to such successor trustee (the "1993 Mortgage
Trustee"), as the basis for the authentication and delivery under the 1993
Mortgage of a series of securities. As provided in the 1993 Mortgage, the
Collateral Series M Bonds will be registered in the name of the 1993 Mortgage
Trustee or its nominee and will be owned and held by the 1993 Mortgage Trustee,
subject to the provisions of the 1993 Mortgage, for the benefit of the holders
of all securities from time to time outstanding under the 1993 Mortgage, and the
Company shall have no interest therein.

                  Any payment or deemed payment by the Company under the 1993
Mortgage of the principal of the securities which shall have been authenticated
and delivered under the 1993 Mortgage on the basis of the issuance and delivery
to the 1993 Mortgage Trustee of Collateral Series M Bonds (other than by the
application of the proceeds of a payment in respect of such Collateral Series M
Bonds) shall, to the extent thereof, be deemed to satisfy and discharge the
obligation of the Company, if any, to make a payment of principal of such
Collateral Series M Bonds which is then due.

                  The Trustee may conclusively presume that the obligation of
the Company to pay the principal of the Collateral Series M Bonds as the same
shall become due and payable shall have been fully satisfied and discharged
unless and until it shall have received a written notice from the 1993 Mortgage
Trustee, signed by an authorized officer thereof, stating that the principal of
specified Collateral Series M Bonds has become due and payable and has not been
fully paid, and specifying the amount of funds required to make such payment.

                  Each Collateral Series M Bond shall be dated as of the date of
its authentication.

                  The Collateral Series M Bonds shall be issued as fully
registered bonds only, in denominations of $1,000 and multiples thereof.

                  The Collateral Series M Bonds shall be registerable and
exchangeable at the office or agency of the Company in the city in which the
principal corporate trust office of the 1993 Mortgage Trustee is located, in the
manner and upon the terms set forth in Section 5 of Article II of the Indenture;
provided, however, that the Collateral Series M Bonds shall not be transferrable
except to a successor trustee under the 1993 Mortgage. No service charge shall
be made for any exchange or transfer of any Collateral Series M Bond.

                                        3

<PAGE>

                  SECTION 2. The text of the Collateral Series M Bonds shall be
substantially in the form attached hereto as Exhibit A.

                  SECTION 3. The Collateral Series M Bonds may be executed by
the Company and delivered to the Trustee and, upon compliance with all
applicable provisions and requirements of the Indenture in respect thereof,
shall be authenticated by the Trustee and delivered (without awaiting the filing
or recording of this Supplemental Indenture) in accordance with the written
order or orders of the Company.

                                  ARTICLE TWO

                   REDEMPTION OF THE COLLATERAL SERIES M BONDS

                  SECTION 1. Each Collateral Series M Bond shall be redeemable
at the option of the Company in whole at any time, or in part from time to time,
prior to maturity, at a redemption price equal to 100% of the principal amount
thereof to be redeemed.

                  SECTION 2. The provisions of Sections 3, 4, 5, 6 and 7 of
Article V of the Indenture shall be applicable to the Collateral Series M Bonds,
except that (a) no publication of notice of redemption of the Collateral Series
M Bonds shall be required and (b) if less than all the Collateral Series M Bonds
are to be redeemed, the Collateral Series M Bonds to be redeemed shall be
selected in the principal amounts designated to the Trustee by the Company, and
except as such provisions may otherwise be inconsistent with the provisions of
this Article Two.

                  SECTION 3. The holder of each and every Collateral Series M
Bond hereby agrees to accept payment thereof prior to maturity on the terms and
conditions provided for in this Article Two.

                                 ARTICLE THREE

                         ACKNOWLEDGMENT OF RIGHT TO VOTE
                           OR CONSENT WITH RESPECT TO
                         CERTAIN AMENDMENTS TO INDENTURE

                  The Company hereby acknowledges the right of the holders of
the Collateral Series M Bonds to vote or consent with respect to any or all of
the modifications to the Indenture referred to in Article Three of the
Supplemental Indenture, dated as of March 1, 1980, irrespective of the fact that
the Bonds of the Second 1987 Series are no longer outstanding; provided,
however, that such acknowledgment shall not impair (a) the right of the Company
to make such modifications without the consent or other action of the holders of
the Bonds of the 2020 Series or the bonds of any other series subsequently
created under the Indenture with respect to which the Company has expressly
reserved such right or (b) the right of the Company to reserve the right to make
such modifications without the consent or other action of the holders of bonds
of one or more, or any or all, series created subsequent to the creation of the
Collateral Series M Bonds.

                                        4

<PAGE>

                                  ARTICLE FOUR

                                   THE TRUSTEE

                  The Trustee accepts the trusts created by this Supplemental
Indenture upon the terms and conditions set forth in the Indenture and this
Supplemental Indenture. The recitals in this Supplemental Indenture are made by
the Company only and not by the Trustee. Each and every term and condition
contained in Article XII of the Indenture shall apply to this Supplemental
Indenture with the same force and effect as if the same were herein set forth in
full, with such omissions, variations and modifications thereof as may be
appropriate to make the same conform to this Supplemental Indenture.

                                  ARTICLE FIVE

                            MISCELLANEOUS PROVISIONS

                  SECTION 1. Subject to the variations contained in Article Two
of this Supplemental Indenture, the Indenture is in all respects ratified and
confirmed and the Principal Indenture, this Supplemental Indenture and all other
indentures supplemental to the Principal Indenture shall be read, taken and
construed as one and the same instrument. Neither the execution of this
Supplemental Indenture nor anything herein contained shall be construed to
impair the lien of the Indenture on any of the properties subject thereto, and
such lien shall remain in full force and effect as security for all bonds now
outstanding or hereafter issued under the Indenture.

                  All covenants and provisions of the Indenture shall continue
in full force and effect and this Supplemental Indenture shall form part of the
Indenture.

                  SECTION 2. If the date for making any payment or the last date
for performance of any act or the exercising of any right, as provided in this
Supplemental Indenture, shall not be a Business Day (as defined in the 1993
Mortgage), such payment may be made or act performed or right exercised on the
next succeeding Business Day with the same force and effect as if done on the
nominal date provided in this Supplemental Indenture.

                  SECTION 3. The terms defined in the Indenture shall, for all
purposes of this Supplemental Indenture, have the meaning specified in the
Indenture except as set forth in Section 4 of this Article or otherwise set
forth in this Supplemental Indenture or unless the context clearly indicates
some other meaning to be intended.

                  SECTION 4. Any term defined in Section 303 of the Trust
Indenture Act of 1939, as amended, and not otherwise defined in the Indenture
shall, with respect to this Supplemental Indenture and the Collateral Series M
Bonds, have the meaning assigned to such term in Section 303 as in force on the
date of the execution of this Supplemental Indenture.

                  SECTION 5. This Supplemental Indenture may be executed in any
number of counterparts, and all of said counterparts executed and delivered,
each as an original, shall constitute but one and the same instrument.

                                        5

<PAGE>

                  IN WITNESS WHEREOF, Public Service Company of Colorado, party
hereto of the first part, has caused its corporate name to be hereunto affixed,
and this instrument to be signed by its President, an Executive Vice President,
a Senior Vice President or a Vice President, and its corporate seal to be
hereunto affixed and attested by its Secretary or an Assistant Secretary for and
in its behalf; and U.S. Bank Trust National Association, the party hereto of the
second part, in evidence of its acceptance of the trust hereby created, has
caused its corporate name to be hereunto affixed, and this instrument to be
signed and its corporate seal to be affixed by one of its Assistant Vice
Presidents and attested by one of its Trust Officers, for and in its behalf, all
as of the day and year first above written.

                                          PUBLIC SERVICE COMPANY OF
                                           COLORADO
          [company seal]
                                          By: /S/ BENJAMIN G.S. FOWKE III
                                             -----------------------------------
                                             Name:  Benjamin G. S. Fowke III
                                             Title: Vice President and Treasurer

ATTEST:  /S/ ANNE M. ZIEBELL
       --------------------------------
       Name:  Anne M. Ziebell
       Title: Assistant Secretary

STATE OF MINNESOTA               )
                                 ) ss.:
CITY OF MINNEAPOLIS              )

                  On this 8th day of May, 2003, before me, Sharon M.
Quellhorst, a duly authorized Notary Public in and for said City in the State
aforesaid, personally appeared Benjamin G. S. Fowke III and Anne M. Ziebell to
me known to be a Vice President and Treasurer and the Assistant Secretary,
respectively, of PUBLIC SERVICE COMPANY OF COLORADO, a corporation organized and
existing under the laws of the State of Colorado, one of the corporations that
executed the within and foregoing instrument; and the said Vice President and
Treasurer and Assistant Secretary severally acknowledged the said instrument to
be the free and voluntary act and deed of said corporation, for the uses and
purposes therein mentioned, and on oath stated that they were authorized to
execute said instrument and that the seal affixed thereto is the corporate seal
of said corporation.

                  IN WITNESS WHEREOF, I have hereunto set my hand and affixed my
official seal the day and year first above written.

                                              /S/ SHARON M. QUELLHORST
                                          --------------------------------------
                                          Name: Sharon M. Quellhorst
          [notary seal]                   Notary Public, State of Colorado
                                          Commission Expires: January 31, 2005

                                        6

<PAGE>

                                          U.S. BANK TRUST
                                            NATIONAL ASSOCIATION,
                                                as Trustee

                                          By: /S/ IGNAZIO TAMBURELLO
                                             -----------------------------------
                                             Name:  Ignazio Tamburello
                                             Title: Assistant Vice President

ATTEST: /S/ ADAM BERMAN
       --------------------------------
       Name:  Adam Berman
       Title: Trust Officer

STATE OF NEW YORK                )
                                 ) ss.:
CITY AND COUNTY OF NEW YORK      )

                  On this 8th day of May, 2003 before me, Janet O'Hara, a duly
authorized Notary Public in and for said City and County in the State aforesaid,
personally appeared Ignazio Tamburello and Adam Berman to me known to be an
Assistant Vice President and a Trust Officer, respectively, of U.S. BANK TRUST
NATIONAL Association, a national banking association, one of the corporations
that executed the within and foregoing instrument; and the said Assistant Vice
President and Trust Officer severally acknowledged the said instrument to be the
free and voluntary act and deed of said corporation, for the uses and purposes
therein mentioned, and on oath stated that they were authorized to execute said
instrument and that the seal affixed thereto is the corporate seal of said
corporation.

                  IN WITNESS WHEREOF, I have hereunto set my hand and affixed my
official seal the day and year first above written.

                                              /S/ JANET O'HARA
                                          --------------------------------------
                                          Name: Janet O'Hara
                                          Notary Public, State of New York
                                          Commission Expires: November 3, 2005

                                                      [notary seal]

                                        7

<PAGE>

                                                                       EXHIBIT A

                        FORM OF COLLATERAL SERIES M BOND

         THIS BOND IS NOT TRANSFERABLE EXCEPT TO A SUCCESSOR TRUSTEE UNDER THE
INDENTURE, DATED AS OF OCTOBER 1, 1993, AS SUPPLEMENTED, BETWEEN PUBLIC SERVICE
COMPANY OF COLORADO AND U.S. BANK TRUST NATIONAL ASSOCIATION (FORMERLY FIRST
TRUST OF NEW YORK, NATIONAL ASSOCIATION), AS SUCCESSOR TRUSTEE THEREUNDER.

                       PUBLIC SERVICE COMPANY OF COLORADO

                              FIRST MORTGAGE BOND,

                               Collateral Series M

                                    DUE [  ]

REGISTERED                                                            REGISTERED

No. 1                                                               $350,000,000

         FOR VALUE RECEIVED, PUBLIC SERVICE COMPANY OF COLORADO, a corporation
organized and existing under the laws of the State of Colorado (hereinafter
sometimes called the "Company"), promises to pay to U.S. Bank Trust National
Association (formerly known as First Trust of New York, National Association),
as successor trustee (the "1993 Mortgage Trustee") under the Indenture, dated as
of October 1, 1993 (the "1993 Mortgage"), of the Company, or registered assigns,
Three Hundred Fifty Million Dollars on [ ], at the office or agency of the
Company in the city in which the principal corporate trust office of the 1993
Mortgage Trustee is located. This bond shall not bear interest. The principal of
this bond shall be payable in any coin or currency of the United States of
America which at the time of payment shall be legal tender for the payment of
public and private debts.

         Any payment or deemed payment by the Company under the 1993 Mortgage of
the principal of securities which shall have been authenticated and delivered
under the 1993 Mortgage on the basis of the issuance and delivery to the 1993
Mortgage Trustee of this bond (the "1993 Mortgage Securities") (other than by
the application of the proceeds of a payment in respect of this bond) shall, to
the extent thereof, be deemed to satisfy and discharge the obligation of the
Company, if any, to make a payment of principal of this bond which is then due.

         This bond is one of an issue of bonds of the Company, issued and to be
issued in one or more series under and equally and ratably secured (except as
any sinking, amortization, improvement or other fund, established in accordance
with the provisions of the indenture hereinafter mentioned, may afford
additional security for the bonds of any particular series) by a certain
indenture, dated as of December 1, 1939, made by the Company to U.S. BANK TRUST
NATIONAL ASSOCIATION (formerly First Trust of New York, National Association),
as

                                   EXHIBIT A-1

<PAGE>

successor trustee (hereinafter called the "Trustee") to Morgan Guaranty Trust
Company of New York (formerly Guaranty Trust Company of New York), as amended
and supplemented by several indentures supplemental thereto, including the
Supplemental Indenture dated as of May 1, 2003 (said Indenture as amended and
supplemented by said indentures supplemental thereto being hereinafter called
the "Indenture"), to which Indenture reference is hereby made for a description
of the property mortgaged, the nature and extent of the security, the rights and
limitations of rights of the Company, the Trustee, and the holders of said
bonds, under the Indenture, and the terms and conditions upon which said bonds
are secured, to all of the provisions of which Indenture and of all indentures
supplemental thereto in respect of such security, including the provisions of
the Indenture permitting the issue of bonds of any series for property which,
under the restrictions and limitations therein specified, may be subject to
liens prior to the lien of the Indenture, the holder, by accepting this bond,
assents. To the extent permitted by and as provided in the Indenture, the rights
and obligations of the Company and of the holders of said bonds (including those
pertaining to any sinking or other fund) may be changed and modified, with the
consent of the Company, by the holders of at least 75% in aggregate principal
amount of the bonds then outstanding (excluding bonds disqualified from voting
by reason of the Company's interest therein as provided in the Indenture);
provided, however, that without the consent of the holder hereof no such
modification or alteration shall be made which will extend the time of payment
of the principal of this bond or reduce the principal amount hereof or effect
any other modification of the terms of payment of such principal or will reduce
the percentage of bonds required for the aforesaid actions under the Indenture.
The Company has reserved the right to amend the Indenture without any consent or
other action by holders of any series of bonds created after October 31, 1975
(including this series) so as to change 75% in the foregoing sentence to 60% and
to change certain procedures relating to bondholders' meetings. This bond is one
of a series of bonds designated as the First Mortgage Bonds, Collateral Series
M, of the Company.

         This bond shall be redeemable at the option of the Company in whole at
any time, or in part from time to time, prior to maturity, at a redemption price
equal to 100% of the principal amount thereof to be redeemed.

         The principal of this bond may be declared or may become due before the
maturity hereof, on the conditions, in the manner and at the times set forth in
the Indenture, upon the happening of an event of default as therein provided.

         This bond is not transferable except to a successor trustee under the
1993 Mortgage, any such transfer to be made at the office or agency of the
Company in the city in which the principal corporate trust office of the 1993
Mortgage Trustee is located, upon surrender and cancellation of this bond, and
thereupon a new bond of this series of a like principal amount will be issued to
the transferee in exchange therefor, as provided in the Indenture. The Company,
the Trustee, any paying agent and any registrar may deem and treat the person in
whose name this bond is registered as the absolute owner hereof for the purpose
of receiving payment and for all other purposes. This bond, alone or with other
bonds of this series, may in like manner be exchanged at such office or agency
for one or more new bonds of this series of the same aggregate principal amount,
all as provided in the Indenture. No service charge shall be made to any holder
of any bond of this series for any exchange or transfer of bonds.

                                   EXHIBIT A-2

<PAGE>

         No recourse under or upon any covenant or obligation of the Indenture,
or of any bonds thereby secured, or for any claim based thereon, or otherwise in
any manner in respect thereof, shall be had against any incorporator, subscriber
to the capital stock, shareholder, officer or director, as such, of the Company,
whether former, present or future, either directly, or indirectly through the
Company or the Trustee, by the enforcement of any subscription to capital stock,
assessment or otherwise, or by any legal or equitable proceeding by virtue of
any statute or otherwise (including, without limiting the generality of the
foregoing, any proceeding to enforce any claimed liability of shareholders of
the Company based upon any theory of disregarding the corporate entity of the
Company or upon any theory that the Company was acting as the agent or
instrumentality of the shareholders), any and all such liability of
incorporators, shareholders, subscribers, officers and directors, as such, being
released by the holder hereof, by the acceptance of this bond, and being
likewise waived and released by the terms of the Indenture under which this bond
is issued.

         This bond shall not be valid or become obligatory for any purpose until
the certificate of authentication endorsed hereon shall have been signed by U.S.
Bank Trust National Association, or its successor, as Trustee under the
Indenture.

         IN WITNESS WHEREOF, Public Service Company of Colorado has caused this
bond to be signed in its name by a Vice President and its corporate seal to be
affixed hereto and attested by its Secretary or an Assistant Secretary.

Dated:                                    PUBLIC SERVICE COMPANY OF
                                          COLORADO

                                          By:________________________________
                                               Vice President and Treasurer

ATTEST:________________________
        Assistant Secretary

                          CERTIFICATE OF AUTHENTICATION

         This is one of the securities of the series designated therein referred
to in the within-mentioned Supplemental Indenture.

Dated:                                    U.S. BANK TRUST
                                          NATIONAL ASSOCIATION,
                                                AS TRUSTEE

                                          By:________________________________
                                                           Authorized Officer

                                   EXHIBIT A-3

<PAGE>

                                                                      SCHEDULE A

                             SUPPLEMENTAL INDENTURES

<TABLE>
<CAPTION>
     DATE OF                                                                     PRINCIPAL
   SUPPLEMENTAL                                                  PRINCIPAL        AMOUNT
    INDENTURE                    SERIES OF BONDS               AMOUNT ISSUED    OUTSTANDING
    ---------                    ---------------               -------------    -----------
<S>                           <C>                             <C>               <C>
March 14, 1941                         None                         --              --
May 14, 1941                           None                         --              --
April 28, 1942                         None                         --              --
April 14, 1943                         None                         --              --
April 27, 1944                         None                         --              --
April 18, 1945                         None                         --              --
April 23, 1946                         None                         --              --
April 9, 1947                          None                         --              --
June 1, 1947*                 2-7/8% Series due 1977          $    40,000,000      None
April 1, 1948                          None                         --              --
May 20, 1948                           None                         --              --
October 1, 1948               3-1/8% Series due 1978               10,000,000      None
April 20, 1949                         None                         --              --
April 24, 1950                         None                         --              --
April 18, 1951                         None                         --              --
October 1, 1951               3-1/4% Series due 1981               15,000,000      None
April 21, 1952                         None                         --              --
December 1, 1952                       None                         --              --
April 15, 1953                         None                         --              --
April 19, 1954                         None                         --              --
October 1, 1954*              3-1/8% Series due 1984               20,000,000      None
April 18, 1955                         None                         --              --
April 24, 1956                         None                         --              --
May 1, 1957*                  4-3/8% Series due 1987               30,000,000      None
April 10, 1958                         None                         --              --
May 1, 1959                   4-5/8% Series due 1989               20,000,000      None
April 18, 1960                         None                         --              --
April 19, 1961                         None                         --              --
October 1, 1961               4-1/2% Series due 1991               30,000,000      None
March 1, 1962                 4-5/8% Series due 1992                8,800,000      None
June 1, 1964                  4-1/2% Series due 1994               35,000,000      None
May 1, 1966                   5-3/8% Series due 1996               35,000,000      None
July 1, 1967*                 5-7/8% Series due 1997               35,000,000      None
July 1, 1968*                 6-3/4% Series due 1998               25,000,000      None
April 25, 1969                         None                         --              --
</TABLE>

                                  SCHEDULE A-1

<PAGE>

<TABLE>
<CAPTION>
     DATE OF                                                                     PRINCIPAL
   SUPPLEMENTAL                                                 PRINCIPAL         AMOUNT
    INDENTURE                    SERIES OF BONDS               AMOUNT ISSUED    OUTSTANDING
    ---------                    ---------------               -------------    -----------
<S>                      <C>                                   <C>              <C>
April 21, 1970                         None                         --               --
September 1, 1970             8-3/4% Series due 2000              35,000,000        None
February 1, 1971              7-1/4% Series due 2001              40,000,000        None
August 1, 1972                7-1/2% Series due 2002              50,000,000        None
June 1, 1973                  7-5/8% Series due 2003              50,000,000        None
March 1, 1974               Pollution Control Series A            24,000,000        None
December 1, 1974            Pollution Control Series B            50,000,000        None
October 1, 1975               9-3/8% Series due 2005              50,000,000        None
April 28, 1976                         None                        --                --

April 28, 1977                         None                        --                --
November 1, 1977*             8-1/4% Series due 2007              50,000,000        None
April 28, 1978                         None                        --                --
October 1, 1978               9-1/4% Series due 2008              50,000,000        None
October 1, 1979*            Pollution Control Series C            50,000,000        None
March 1, 1980*                 15% Series due 1987                50,000,000        None
April 28, 1981                         None                        --                --
November 1, 1981*           Pollution Control Series D            27,380,000        None
December 1, 1981*            16-1/4% Series due 2011              50,000,000        None
April 29, 1982                         None                        --                --
May 1, 1983*                Pollution Control Series E            42,000,000        None

April 30, 1984                         None                        --                --
March 1, 1985*                 13% Series due 2015                50,000,000        None
November 1, 1986*           Pollution Control Series F            27,250,000        None
May 1, 1987*                  8.95% Series due 1992               75,000,000        None
July 1, 1990*                 9-7/8% Series due 2020              75,000,000        None
December 1, 1990*          Secured Medium-Term Notes,            191,500,000**      None
                                    Series A
March 1, 1992*              8-1/8% Series due 2004 and           100,000,000    100,000,000
                              8-3/4% Series due 2022             150,000,000    144,840,000
April 1, 1993*              Pollution Control Series G            79,500,000     79,500,000
June 1, 1993*               Pollution Control Series H            50,000,000     50,000,000
November 1, 1993*              Collateral Series A               134,500,000    134,500,000

January 1, 1994*         Collateral Series B due 2001 and        102,667,000        None
                           Collateral Series B due 2024          110,000,000    110,000,000
September 2, 1994                      None                        --                --
(Appointment of
Successor Trustee)
May 1, 1996                    Collateral Series C               125,000,000   125,000,000
</TABLE>

                                  SCHEDULE A-2

<PAGE>

<TABLE>
<CAPTION>
     DATE OF                                                                     PRINCIPAL
   SUPPLEMENTAL                                                 PRINCIPAL         AMOUNT
    INDENTURE                    SERIES OF BONDS               AMOUNT ISSUED    OUTSTANDING
    ---------                    ---------------               -------------    -----------
<S>                            <C>                             <C>              <C>
November 1, 1996               Collateral Series D              250,000,000     175,000,000
February 1, 1997               Collateral Series E              150,000,000         None
April 1, 1998                  Collateral Series F              250,000,000         None
August 15, 2002                Collateral Series G               48,750,000      48,750,000
September 1, 2002              Collateral Series H              600,000,000         None
September 15, 2002             Collateral Series I              530,000,000     530,000,000
April 1, 2003                  Collateral Series J              600,000,000     600,000,000
March 1, 2003                  Collateral Series K              250,000,000     250,000,000
</TABLE>

------------------
* Contains amendatory provisions

** $200,000,000 authorized

                                  SCHEDULE A-3

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00052-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00052-of-00352.parquet"}]]