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                                                                   Exhibit 10.21


                              TAX-SHARING AGREEMENT


         This Tax-Sharing Agreement is entered into as of November 24, 1997,
between Western Resources, Inc., a Kansas corporation ("Western Resources"), and
Protection One, Inc., a Delaware corporation ("Protection One"), with reference
to the following facts:

         A. Concurrently with the execution and delivery hereof, Protection One
is issuing to Western Resources an aggregate of 68,673,402 shares of the common
stock, par value $.01 per share, of Protection One, pursuant to a Contribution
Agreement dated as of July 30 1997, as amended, by and between Western Resources
and Protection One (the "Contribution Agreement").

         B. As contemplated by the Contribution Agreement, Western Resources and
Protection One desire to enter into this Tax-Sharing Agreement to provide for
the payment of tax liabilities and provide for certain other tax matters.

         NOW, THEREFORE, the parties hereto hereby agree that income taxes (U.S.
and state) shall be accounted for and tax liabilities shall be accounted for
between Protection One and its subsidiaries, on the one hand, and Western
Resources and its subsidiaries, on the other, in accordance with the Tax Sharing
and Allocation Policy, a copy of which is attached hereto, with Protection One
and its subsidiaries constituting a separate "subsidiary group" for purposes of
such policy.

         IN WITNESS WHEREOF, Western Resources and Protection One have executed
this Agreement as of the date first above written.

                                    WESTERN RESOURCES, INC.

                                    By:    /s/ Steve Kitchen
                                           -----------------------------------
                                    Title: Executive Vice President and Chief
                                           Financial Officer
                                           -----------------------------------



                                    PROTECTION ONE, INC.


                                    By:    /s/ James A. Mackenzie
                                           -----------------------------------
                                    Title: President and CEO
                                           -----------------------------------
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SUBJECT                                        SECTION NO.                       PAGE
Tax Sharing and Allocation Policy              6.90                              1 of 3
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                        TAX SHARING AND ALLOCATION POLICY

STATEMENT OF FACTS
------------------


         This policy statement will set forth the general guidelines with
respect to the accounting for income taxes (U.S and state) and the allocation of
the consolidated tax liabilities among the subsidiary groups.

         Western Resources, Inc. files a consolidated return with its
subsidiaries, all of which are 100 percent owned. In most jurisdictions, cash
subsidiary group files separate company state income tax returns; however, a
consolidated Kansas return is filed.

Subsidiary Groups
-----------------


         The consolidated U.S. and any consolidated state tax liability shall be
allocated among the following subsidiary groups:

          o    Western Resources, Inc.

          o    Kansas Gas and Electric Company and Subsidiaries

          o    Astra Resources, and Subsidiaries


Tax Provision
-------------


         Each subsidiary group shall calculate its U.S. and state tax provision
and liability on stand-alone separate company basis. Such provision shall be
recorded at the highest U.S. and state tax rate. This means that each subsidiary
group shall calculate its tax liability for their subsidiary group as if it was
a separate entity. The separate calculation includes a separate calculation for
all taxes, including alternative minimum tax (AMT).
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         Taxes for any foreign subsidiary owned by any member of the group shall
be recorded at the foreign country's tax rate. If any taxes are required to be
recorded in the U.S. for foreign dividends received or for equity earnings in
subsidiary, said income tax provision shall be calculated by the separate group;
however, the foreign tax credit calculation shall be determined by taking into
consideration any consolidated facts that affect taxation of the foreign source
income. For example, any allocation under SEC. 861 shall be based upon the
allocation made at the consolidated level.

         If a subsidiary or a subsidiary group has a taxable loss or tax benefit
for which a benefit will be derived in the consolidated return, P&L benefit,
both U.S. and state (negative provision - receivable from parent), shall be
recorded by the subsidiary group. The provision calculated shall be made
utilizing the maximum U.S. and state rate for the consolidated jurisdiction. If,
after booking the regular tax benefit, it is determined that an AMT tax would
exist on a separate company basis, the AMT tax must also be recorded. The effect
of this is that the current payable is increased and deferred taxes are
decreased. There will be no P&L effect by recording the AMT tax liability.
Payment for the tax benefit is covered under the section entitled Payment of Tax
Benefits.

Tax Return and Estimated Tax Payments
-------------------------------------


         Each subsidiary or subsidiary group shall pay to the parent two days
prior to the payment date their share of any consolidated U.S. (regular or AMT)
or state income tax payment calculated on a stand-alone basis.

         Western Resources shall make all consolidated tax payments to the
taxing authority. State payments for separate state returns shall be paid by the
subsidiary groups directly to the taxing authority.

Payment of Tax Benefits
-----------------------


         If a subsidiary group generates a taxable loss or other tax benefit
which is utilized in the consolidated return, Western Resources shall pay to
that subsidiary the separate return benefit recorded by that subsidiary group.
If a subsidiary or subsidiary group has a separate company or a group
consolidated net operating loss, and that subsidiary or subsidiary group files a
separate consolidated state return not including Western Resources, no payment
shall be made to that subsidiary or subsidiary group for that separate state
NOL.
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SUBJECT                                        SECTION NO.                       PAGE
Tax Sharing and Allocation Policy              6.90                              3 of 3
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SECTION                                        APPROVED BY                       EFFECTIVE DATE
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Adjustments
-----------


         If, upon examination of the consolidated U.S. or state income tax
return an adjustment to the consolidated tax liability is determined, such
adjustment shall be calculated at the subsidiary group level and the tax and
interest paid to Western Resources. Such payment shall include taxes, penalties,
and interest accruable from the due date of the return to the date or the
deficiency payment.

Recordkeeping
-------------


         Western Resources shall maintain detailed records calculating the
consolidated tax liability and benefits payable to subsidiary groups. Such
records shall also include the detailed record of the cash payments or
intercompany charges for payments to and from parent and subsidiary group.

Separate Returns
----------------


         Any separate state returns shall be the responsibilities of the
subsidiary or the subsidiary group, and any payments, both declaration and
return payments, shall be made directly to the taxing authority by such
subsidiary or subsidiary group.