EXHIBIT 10.5

               SUPPLEMENTAL RETIREMENT BENEFIT PLAN

     This Supplemental Retirement Benefit Plan (the "Plan") is adopted
 effective as of this 17th day of October, 1991, by Mosinee Paper
 Corporation, a Wisconsin corporation, ("Mosinee") for the purposes of
 providing deferred compensation in the form of supplemental retirement
 benefits for San W. Orr, Jr. ("Mr. Orr") in recognition of his service to
 Mosinee as its Chairman of the Board of Directors.

     1.   NORMAL SUPPLEMENTAL RETIREMENT BENEFIT.  Beginning on the first
 day of the first month following the last to occur of (a) Mr. Orr's
 termination of employment with Mosinee or (b) Mr. Orr's 60th birthday, and
 continuing on the first day of each succeeding month, Mosinee shall pay to
 Mr. Orr, if he is then living, a monthly supplemental retirement benefit
 (Mr. Orr's "Normal Supplemental Retirement Benefit") in an amount equal to
 50% of one-twelfth of Mr. Orr's highest final average W-2 compensation for
 the five consecutive calendar year period in which such compensation was
 paid.  Mr. Orr's Normal Supplemental Retirement Benefit shall not be
 reduced or offset by the amount of any other payment then due him from
 Mosinee or any other plan or program now or hereafter maintained by
 Mosinee.

     2.   SURVIVING SPOUSE BENEFIT.  From and after the first day of the
 first month following the later of (a) the month in which Mr. Orr's death
 occurs or (b) the month in which Mr. Orr would have attained his 60th
 birthday if Mr. Orr's death occurs before

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 he has attained age 60, and continuing on the first day of each
 succeeding month, Mosinee shall pay to Mr. Orr's spouse, if then
 living (Mr. Orr's "Surviving Spouse"), a monthly benefit (the 
 "Supplemental Surviving Spouse Benefit") in an amount equal to 50% of
 the Normal Supplemental Retirement Benefit to which Mr. Orr would have
 then been entitled had he then been living.

     3.   CHANGE OF CONTROL OF MOSINEE.

          (a)  In the event a Change of Control of Mosinee occurs prior to
     Mr. Orr's death, Mosinee shall pay to Mr. Orr a lump sum amount equal
     to the present value of Mr. Orr's Normal Supplemental Retirement
     Benefit, as determined hereunder, as of the first day of the first
     month following such Change of Control of Mosinee on which Mr. Orr is
     neither an employee nor a director of Mosinee, whether or not such
     Change of Control occurred prior to the date on which Mr. Orr shall
     have ceased to be an employee or a director of Mosinee.  Upon payment
     of the lump sum amount provided for in this subparagraph (a), Mosinee
     shall have no further obligation to pay any benefits under this Plan.

          (b)  In the event a Change of Control occurs after Mr. Orr's
     death and whether or not the Supplemental Surviving Spouse Benefit
     shall have then become payable, Mosinee shall pay to Mr. Orr's
     Surviving Spouse, if then living, the present value of the unpaid
     Supplemental Surviving Spouse Benefit.  Upon payment of the lump sum
     amount provided for

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     in this subparagraph (b), Mosinee shall have no further obligation to
     pay any benefits under this Plan.

      (c)  For purposes of this Plan, a "Change of Control of Mosinee"
     shall mean:

               (1)  The acquisition by any individual, entity or group
          (within the meaning of Section 13(d)(3) or 14(d)(2) of the
          Securities Exchange Act of 1934, as amended (the "Exchange Act"))
          (a "Person") of beneficial ownership (within the meaning of Rule
          13d-3 promulgated under the Exchange Act) of 20% or more of
          either (A) the then outstanding shares of common stock of Mosinee
          (the "Outstanding Company Common Stock") or (B) the combined
          voting power of the then outstanding voting securities of Mosinee
          entitled to vote generally in the election of directors (the
          "Outstanding Company Voting Securities"); provided, however, that
          for purposes of this subsection (1), the following acquisitions
          shall not constitute a Change of Control:  (I) any acquisition
          directly from Mosinee, (II) any acquisition by Mosinee, (III) any
          acquisition by any employee benefit plan (or related trust)
          sponsored or maintained by Mosinee or any corporation controlled
          by Mosinee or (IV) any acquisition pursuant to a transaction
          which complies with clauses (A), (B) and (C) of subsection (3) of
          this Section 2; or

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               (2)  Individuals who, as of the date hereof, constitute the
          Board (the "Incumbent Board") cease for any reason to constitute
          at least a majority of the Board; provided, however, that any
          individual becoming a director subsequent to the date hereof
          whose election, or nomination for election by Mosinee's
          shareholders, was approved by a vote of at least a majority of
          the directors then comprising the Incumbent Board shall be
          considered as though such individual were a member of the
          Incumbent Board, but excluding, for this purpose, any such
          individual whose initial assumption of office occurs as a result
          of an actual or threatened election contest with respect to the
          election or removal of directors or other actual or threatened
          solicitation of proxies or consents by or on behalf of a Person
          other than the Board; or

               (3)  Consummation by Mosinee of a reorganization, merger,
          share exchange or consolidation or sale or other disposition of
          all or substantially all of the assets of Mosinee or the
          acquisition of assets of another corporation (a "Business
          Combination"), in each case, unless, following such Business
          Combination, (A) all or substantially all of the individuals and
          entities who were the beneficial owners, respectively, of the
          Outstanding Company Common Stock and Outstanding Company Voting
          Securities immediately prior to such

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          Business Combination beneficially own, directly or indirectly,
          more than 60% of, respectively, the then outstanding shares of
          common stock and the combined voting power of the then
          outstanding voting securities entitled to vote generally in the
          election of directors, as the case may be, of the corporation
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          resulting from such Business Combination (including, without
          limitation, a corporation which as a result of such transaction
          owns Mosinee or all or substantially all of Mosinee's assets
          either directly or through one or more subsidiaries) in
          substantially the same proportions as their ownership,
          immediately prior to such Business Combination of the
          Outstanding Company Common Stock and Outstanding Company Voting
          Securities, as the case may be, (B) no Person (excluding any
          employee benefit plan (or related trust) of Mosinee or such
          corporation resulting from such Business Combination)
          beneficially owns, directly or indirectly, 20% or more of,
          respectively, the then outstanding shares of common stock of
          the corporation resulting from such Business Combination
          or the combined voting power of the then outstanding voting
          securities of such corporation except to the extent that such
          ownership existed with respect to Mosinee prior to the Business
          Combination and (C) at least a majority of the members of the
          board of directors of the corporation resulting from such

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          Business Combination were members of the Incumbent Board at the
          time of the execution of the initial agreement, or of the action
          of the Board, providing for such Business Combination; or

               (4)  Approval by the shareholders of Mosinee of a complete
          liquidation or dissolution of Mosinee.

     Notwithstanding the foregoing, neither the approval by the
     shareholders of Mosinee, nor the consummation, of the transactions
     contemplated by that certain Agreement and Plan of Merger, dated as of
     August 24, 1997, by and among Wausau Paper Mills Company, WPM
     Holdings, Inc. and the Company on substantially the terms and
     conditions set forth therein as of August 24, 1997 shall constitute a
     Change of Control for purposes of this Agreement.

          (d)  For purposes of this Plan, the term "Interested Shareholder"
     shall mean any person (other than Mosinee or any of its subsidiaries
     or any member of the Board of Directors as of the effective date of
     this Plan or any affiliate of such person) who first became the
     beneficial owner of 10% or more of the combined voting power of
     Mosinee's then outstanding securities after the effective date of this
     Plan.

          (e)  For purposes of this Plan, the present value of Mr. Orr's
     Normal Supplemental Retirement Benefit or the Supplemental Surviving
     Spouse Benefit shall be determined by reference to the 1983 Individual
     Annuity Mortality Table

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     with an assumed interest rate equal to the "immediate annuity rate"
     as then in effect as determined by the Pension Benefit Guaranty
     Corporation and promulgated in Appendix B to 29 C.F.R.
     <section>2619.65 or any successor regulation adopted for the
     same or substantially similar purpose.

     4.   SUPPLEMENTAL RETIREMENT BENEFITS IN ADDITION TO OTHER RIGHTS AND
 BENEFITS.  The rights and benefits conferred upon Mr. Orr (and Mr. Orr's
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 Surviving Spouse) pursuant to this Plan shall be in addition to all other
 rights and benefits conferred upon Mr. Orr by Mosinee by reason of his
 employment.

     5.   NATURE OF MOSINEE'S OBLIGATIONS AND MR. ORR'S RIGHTS.  Neither
 Mr. Orr nor his Surviving Spouse, if any, shall acquire any right, title
 or interest in the assets of Mosinee by reason of this Plan.  To the
 extent Mr. Orr or his Surviving Spouse shall acquire a right to receive
 payments from Mosinee pursuant to this Plan, such right shall be no
 greater than the right of any unsecured general creditor of Mosinee.

     6.   ASSIGNMENT BY MR. ORR PROHIBITED.  This Plan and Mr. Orr's rights
 and benefits hereunder (and the rights of his Surviving Spouse, if any)
 shall not be subject to voluntary or involuntary sale, pledge,
 hypothecation, transfer or assignment by Mr. Orr or such Surviving Spouse,
 their personal representatives or heirs or any other person or persons or
 organization or organizations succeeding to any of their rights and
 benefits hereunder.

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     7.   FUNDING.  All benefits paid or payable pursuant to the terms of
 this Plan shall be paid out of the general assets of Mosinee.

     8.   CLAIMS PROCEDURE.  The claims procedure set forth in the Mosinee
 Retirement Plan or any successor to such plan is incorporated herein by
 this reference as the claims procedure for this Plan.

     9.   PLAN ADMINISTRATOR.  The plan administrator and named fiduciary
 of the Plan shall be Mosinee.

     10.  BINDING EFFECT.  This Plan shall be binding upon and inure to the
 benefit of (1) Mr. Orr and his Surviving Spouse and their personal
 representatives and heirs and any other person or persons or organization
 or organizations succeeding to any of Mr. Orr's rights or benefits
 hereunder, and (2) Mosinee and its successors and assigns.

     11.  SEVERABILITY.  The invalidity or unenforceability of any
 provision of this Plan shall not invalidate or render unenforceable any
 other provision of this agreement.

     12.  GOVERNING LAW.  This Plan shall be governed by the Employee
 Retirement Income Security Act of 1974, as amended, and to the extent not
 preempted by such Act, by the laws of the State of Wisconsin.

     IN WITNESS WHEREOF, Mosinee has caused this agreement to be executed
 by its President thereunto duly authorized as of the day and year first
 above written.

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                                   MOSINEE PAPER CORPORATION


                                  By:________________________________
                                     Richard L. Radt
                                     As its President

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