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                                                                    EXHIBIT 4.15

                           AGREEMENT WITH RESPECT TO
                             CONVERTIBLE DEBENTURES
                          OF KIEWIT MATERIALS COMPANY

     THIS AGREEMENT, made and entered into this   day of           , 20  , by
and between                , hereinafter referred to as the Debentureholder, and
KIEWIT MATERIALS COMPANY a Delaware corporation, hereinafter referred to as the
Corporation;

                                  WITNESSETH:

     WHEREAS, it has been and is the policy of the Corporation, as being in its
best interest, to restrict the issuance and holding of its corporate convertible
debentures, hereinafter referred to as debentures; and

     WHEREAS, the Debentureholder, being presently qualified to hold debentures,
desires to be issued debentures of the Corporation to be held subject to the
conditions and restrictions required to effect the aforesaid policy as set forth
hereinafter;

     NOW THEREFORE, in consideration of the issuance of debentures to the
Debentureholder and for other good and valuable consideration, the receipt
whereof is acknowledged by each of the parties hereto, it is agreed by and
between the parties as follows:

          (1) Debentures Subject to Agreement.  Unless otherwise specifically
     set forth in a separate written agreement between the Corporation and the
     Debentureholder, this Agreement shall apply to all debentures issued to the
     Debentureholder on or before the date of this Agreement and any additional
     debentures which are issued to the Debentureholder after the date of this
     Agreement pursuant to an indenture, dated as of           , 2000 (the
     "Indenture"), executed and delivered by the Corporation and UMB Bank, N.A.,
     as Trustee. This Agreement supersedes any previous agreement between the
     Corporation and the Debentureholder relating to such debentures and the
     sale or repurchase of such debentures by the Corporation. All capitalized
     terms used and not otherwise defined herein shall have the meanings
     ascribed to these terms in the Indenture.

          (2) Purchase of Debentures Upon Debentureholder's Proposed Disposition
     of Debentures.  Except for pledges of debentures as collateral for loans in
     connection with the ownership of the debentures, the Debentureholder shall
     not give, sell, assign, pledge, encumber, hypothecate, transfer or
     otherwise dispose of any debentures subject to this Agreement, without
     first offering in writing to sell the debentures to the Corporation. The
     offer to sell the debentures to the Corporation by the Debentureholder
     shall be accepted by the Corporation and a notice of acceptance shall be
     given to the Debentureholder within 30 days following receipt of the offer
     from the Debentureholder.

          (3) Purchase of Debentures Upon Termination of Debentureholder's
     Employment or Debentureholder's Death.

          (a) In the event that the Debentureholder's employment is terminated
     for any reason other than the Debentureholder's death, the Debentureholder
     shall sell the Corporation all of the debentures owned by the
     Debentureholder, and the Corporation shall purchase all of such debentures
     in accordance with the terms of this Agreement. Notice of the Corporation's
     intent to purchase such debentures shall be given within 90 days from the
     date the employment has ceased.

          (b) In the event that:

             (i) the Debentureholder dies prior to the expiration date of the
        Regular Conversion Period with respect to any debentures held by the
        Debentureholder, and the Debentureholder's representative or estate, as
        the case may be, fails to convert such debentures prior to the earlier
        of (a) the 30-day period following the Debentureholder's death, or (b)
        the expiration of such Regular Conversion Period, in accordance with the
        terms thereof and the Indenture; or
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             (ii) the Debentureholder dies on or after the expiration date of
        such Regular Conversion Period,

     the Debentureholder's representative or estate, as the case may be, shall
     sell the Corporation all of such debentures owned by the Debentureholder,
     and the Corporation shall purchase all of such debentures in accordance
     with the terms of this Agreement. Notice of the Corporation's intent to
     purchase such debentures shall be given:

             (x) in the event that the Debentureholder dies prior to the
        expiration date of such Regular Conversion Period and the
        Debentureholder's representative or estate, as the case may be, fails to
        convert the Debentureholder's debentures as provided in subparagraph (i)
        above, within 180 days from the date which is 30 days following the date
        of the Debentureholder's death; and

             (y) in the event that the Debentureholder dies on or after the
        expiration date of such Regular Conversion Period, within 180 days from
        the date of the Debentureholder's death.

     For purposes of this Section 3:

     "Employment" is defined to mean employment by the Corporation, one of its
     subsidiaries or a joint venture in which the Corporation and/or its
     subsidiaries have a 20 percent or more interest; provided, however, that
     prior to the distribution by Peter Kiewit Sons', Inc.("Kiewit") as a
     dividend of shares of common stock of the Corporation to Kiewit's
     stockholders, "Employment" shall also mean employment by Kiewit, one of
     Kiewit's subsidiaries or a joint venture in which Kiewit and/or its
     subsidiaries have a 20 percent or more interest or employment by KCP, Inc.
     or any one of KCP, Inc.'s subsidiaries or a joint venture in which KCP,
     Inc. and/or its subsidiaries have a 20 percent or more interest; and

     "Subsidiaries" of the Corporation, Kiewit or KCP, Inc. shall mean any
     corporation in which such entities own, directly or indirectly, at least 20
     percent of the outstanding capital stock, based on the total dollar value
     of outstanding stock if there is more than one class of stock outstanding.

          (4) Purchase Price and Payment for Debentures.  The purchase price
     shall be at a price equal to the principal amount of the debentures plus
     accrued and unpaid interest to the date of purchase. The purchase price
     shall be paid to the Debentureholder, or such other person as may be
     legally entitled thereto, within 60 days after the date of mailing of
     notice by the Corporation as provided in paragraphs (2) and (3); provided,
     that the Corporation received the certificate or certificates evidencing
     the debentures subject to purchase by the Corporation, endorsed in blank or
     accompanied by appropriate transfer powers executed in blank, and
     accompanied by such other evidence of authority as may reasonably be
     required. In the event of failure to deliver to the Corporation the
     certificate or certificates for the debentures subject to purchase with
     required evidence of authority within 30 days after the date of mailing the
     notice by the Corporation as provided in paragraphs (2) and (3), the
     Secretary of the Corporation shall be authorized to cancel such
     certificates on the books of the Corporation and such debentures shall be
     deemed to be no longer outstanding. The holder of such debentures shall
     thereafter have no further interest as a holder of debentures with respect
     to such debentures except to receive the purchase price therefor. It is
     further understood and agreed that the Corporation shall be authorized to
     deduct from the purchase price any amount due it or others from the
     Debentureholder pertaining to the debentures.

          (5) Debentures to be Acquired by Corporation from Debentureholder.  It
     is agreed by the parties that in the event any debenture is tendered by the
     Debentureholder to the Corporation, the Corporation shall purchase all of
     the tendered debentures, and in addition thereto, may, at its option,
     purchase all or any part of such other debentures then owned by the
     Debentureholder.

          (6) Notices.  Any notices required or permitted to be given under this
     Agreement shall be in writing and shall be sufficient if delivered in
     person or sent by certified mail, return receipt requested. The notice to
     the Debentureholder or the Debentureholder's personal representatives, if
     mailed, shall be sent to the Debentureholder's last known address. The
     notice to the Corporation shall be delivered or mailed to the Secretary,
     Kiewit Materials Company, Kiewit Plaza, Omaha, Nebraska 68131.

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          (7) Governing Law.  This Agreement shall be governed in all respects
     by the laws of the State of Nebraska.

          (8) Binding Effect.  This Agreement shall inure to the benefit of and
     be binding upon the heirs, personal representatives and assigns of the
     Debentureholder and upon the successors and assigns of the Corporation.

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

<TABLE>
<S>                                                    <C>
WITNESS:

-----------------------------------------------------  -----------------------------------------------------
                                                       Name: [Debentureholder]

ATTEST:                                                KIEWIT MATERIALS COMPANY
-----------------------------------------------------  By:
                                                       -----------------------------------------------------
                                                           Name:
                                                           Title:
</TABLE>

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