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                                                                   EXHIBIT 10.20


                       FIFTH AMENDMENT TO PARENT GUARANTY

                  This Fifth Amendment to Parent Guaranty (the "Amendment") is
entered into as of June __, 2002, to a certain Second Amended and Restated
Parent Guaranty dated as of August 1, 1999, as amended by a certain Amendment to
Parent Guaranty dated as of September 29, 2000, as amended by a certain Second
Amendment to Parent Guaranty and Waiver dated as of March 13, 2001, as amended
by a certain Third Amendment to Parent Guaranty dated as of April 12, 2001, and
as amended by a certain Fourth Amendment to Parent Guaranty dated as of January
18, 2002 and effective as of September 30, 2001 (collectively, the "Parent
Guaranty") issued by Caraustar Industries, Inc., a North Carolina corporation
(the "Guarantor"), in favor of Toronto Dominion (Texas), Inc., as administrative
agent for the Lenders and the Issuing Bank (the "Administrative Agent").

                                   WITNESSETH:

                  WHEREAS, an affiliate of the Administrative Agent has issued
for the account of Standard Gypsum, L.P., a Delaware limited partnership and the
successor by conversion to Standard Gypsum, L.L.C., a Texas limited liability
company (the "Borrower"), a letter of credit in the aggregate original face
amount of $46,643,014 (the "First Letter of Credit"), pursuant to a
Reimbursement Agreement (the "First Reimbursement Agreement") dated as of May 1,
1999 between the Borrower and the issuer of the Letter of Credit (the "Issuing
Bank"); and

                  WHEREAS, the Issuing Bank has also issued for the account of
the Borrower an additional letter of Credit in the aggregate original face
amount of $10,095,891 (the "Second Letter of Credit" and, collectively with the
First Letter of Credit, the "Letter of Credit"), pursuant to a Reimbursement
Agreement (the "Second Reimbursement Agreement" and, collectively with the First
Reimbursement Agreement, the "Reimbursement Agreement") dated as of August 1,
1999 between the Borrower and Issuing Bank; and

                  WHEREAS, Toronto Dominion (Texas), Inc. acts as Administrative
Agent for itself and for the benefit of the Issuing Bank in connection with the
transactions contemplated by the Reimbursement Agreement; and

                  WHEREAS, the Borrower is a fifty percent (50%) subsidiary of
the Guarantor and the Guarantor, in connection with the transactions
contemplated by the Reimbursement Agreement, has agreed to guarantee fifty
percent (50%) of the obligations and covenants of the Borrower under the
Reimbursement Agreement and the other Loan Documents (the Reimbursement
Agreement and the other Loan Documents as previously executed and as amended,
modified or extended from time to time, the "Guaranteed Agreements"); and


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                  WHEREAS, the Guarantor, certain of its subsidiaries, the
Lenders thereunder, and Bank of America, N.A., as administrative agent, are
parties to that certain Credit Agreement dated as of March 29, 2001 (as amended,
restated or otherwise modified from time to time, the "Guarantor Credit
Agreement"); and

                  WHEREAS, the parties to the Guarantor Credit Agreement have
agreed to amend the provisions thereof and, in connection therewith, to enter
into a Security Agreement (the "Security Agreement") under which the Guarantor
and its subsidiaries party thereto will provide Bank of America, N.A., as
administrative agent, and the Lenders thereunder with a "springing" lien on
certain of their assets, and such parties have further agreed that the
Administrative Agent is an intended third party beneficiary, for itself and on
behalf of the Issuing Bank, of such "springing" lien and shall share in the
distribution of proceeds from any recovery from such assets in accordance with
the provisions of the Security Agreement; and

         WHEREAS, the Guarantor has requested that the Administrative Agent, the
Lenders and the Issuing Bank agree to amend certain provisions of the Parent
Guaranty, and the Administrative Agent, for itself and on behalf of the Lenders
and the Issuing Bank, has agreed to such amendments on the terms and conditions
set forth herein;

                  NOW, THEREFORE, in consideration of the foregoing premises and
other good and valuable consideration, the receipt and sufficiency of which is
acknowledged, the parties hereby agree that all capitalized terms not otherwise
defined herein shall have the meanings ascribed to such terms in the Parent
Guaranty and further agree as follows:

         1.       Amendment and Restatement of Section 18(a) of the Parent
Guaranty.

                  (a)      Section 18 of the Parent Guaranty is hereby amended
and restated by deleting the existing Section 18(a)(i) in its entirety and by
substituting the following therefor:

                           "(i) At all times after the Fourth Amendment
                  Effective Date (as defined in the Credit Agreement dated as of
                  March 29, 2001 among the Guarantor, certain of its
                  subsidiaries, the Lenders thereunder, and Bank of America,
                  N.A., as Administrative Agent (as in effect on the Effective
                  Date of the Fifth Amendment to this Guaranty, the "Guarantor
                  Credit Agreement")), the Guarantor and the other Credit
                  Parties (as defined in the Guarantor Credit Agreement) shall
                  not permit Tangible Net Worth to be less than the TNW Floor
                  (as defined below) plus, as of the end of each fiscal quarter,
                  commencing with the end of the first fiscal quarter ending
                  after the Fourth Amendment Effective Date, (i) 50% of Net
                  Income (to the extent positive) for the fiscal quarter then
                  ended (or, with respect to the fiscal quarter in which the JS
                  Industrial Packaging Group Acquisition (as defined below)
                  occurs, for the portion of the fiscal quarter occurring after


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                  the date such acquisition is consummated), such increases to
                  be cumulative, and (ii) 100% of the net cash proceeds of
                  equity issuances during the fiscal quarter then ended (or,
                  with respect to the fiscal quarter in which the JS Industrial
                  Packaging Group Acquisition occurs, for the portion of the
                  fiscal quarter occurring after the date such acquisition is
                  consummated), such increases to be cumulative.

                  "For purposes hereof, "TNW Floor" shall mean (A) initially,
                  $108,900,000 and (B) upon the consummation of the JS
                  Industrial Packaging Group Acquisition, 90% of actual Tangible
                  Net Worth as of the date of such consummation (and after
                  giving effect thereof), as calculated in good faith by the
                  Guarantor and as certified in writing to Bank of America,
                  N.A., as administrative agent under the Guarantor Credit
                  Agreement, on the date of such consummation by a responsible
                  officer of the Guarantor. "JS Industrial Packaging Group
                  Acquisition" shall mean the Guarantor's acquisition from
                  Jefferson Smurfit Corporation of the business referred to as
                  the "JS Industrial Packaging Group" for an aggregate
                  consideration of approximately $90,000,000 (plus approximately
                  $5,000,000 of transaction costs)."

                  (b)      Section 18 of the Parent Guaranty is hereby further
amended and restated by (i) deleting the phrase "Guarantor's Credit Agreement"
in the penultimate sentence Section 18(a)(iii) and by substituting therefor the
phrase "Guarantor Credit Agreement", and (ii) deleting the final sentence of
Section 18(a)(iii) in its entirety.

         2.       Amendment and Restatement of Section 18(b) of the Parent
Guaranty. Section 18 of the Parent Guaranty is hereby amended and restated by
deleting the existing Section 18(b) in its entirety and by substituting the
following therefor:

                           "(b) The Guarantor agrees that it shall pay a fee in
                  favor of the Administrative Agent for the benefit of the
                  Issuing Bank, commencing on the effective date of the Fifth
                  Amendment to this Guaranty, payable at the times and in the
                  manner provided for the payment of Letter of Credit fees
                  pursuant to Section 2.3 of the Reimbursement Agreement, on
                  fifty percent (50%) of the remaining face amount of the Letter
                  of Credit, at a rate equal to the higher of (i) the
                  "Applicable Percentage" for "Offshore Rate Loans," as those
                  terms are defined in the Guarantor Credit Agreement, or (ii)
                  the interest rate per annum equal to the per annum Letter of
                  Credit fee that would be paid by Guarantor if its long-term
                  senior unsecured debt alone were the basis for the application
                  of the Pricing Grid contained in Section 2.3(a) of the
                  Reimbursement Agreement, less, in either case, the rate set
                  forth for the Letter of Credit fees in the Reimbursement
                  Agreement."



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         3.       Representations and Warranties. The Guarantor hereby
represents and warrants in favor of the Administrative Agent on behalf of the
Lenders and Issuing Bank that:

                           (i)      each representation and warranty set forth
                  in the Parent Guaranty is hereby restated and affirmed as true
                  and correct on the date hereof;

                           (ii)     the Guarantor has the corporate power and
                  authority (a) to enter into this Amendment, and (b) to do all
                  acts and things as are required or contemplated hereunder to
                  be done, observed and performed by it;

                           (iii)    this Amendment has been duly authorized,
                  validly executed and delivered by the Guarantor and the Parent
                  Guaranty, as amended by this Amendment, constitutes the legal,
                  valid and binding obligation of the Guarantor, enforceable
                  against it and in accordance with its terms; and

                           (iv)     the execution and delivery of this Amendment
                  and performance by the Guarantor of its obligations under the
                  Parent Guaranty, as amended hereby, do not and will not
                  require the consent or approval of any regulatory authority or
                  governmental authority or agency having jurisdiction over the
                  Guarantor which has not already been obtained and will not be
                  in contravention of or in conflict with the Certificate of
                  Incorporation or By-laws of the Guarantor or the provisions of
                  any Applicable Law or any material indenture, agreement or
                  other instrument to which the Guarantor is party or by which
                  its assets or properties are bound or affected.

         4.       Conditions Precedent to Closing. This Amendment shall be
deemed closed as of the date first written above, provided that each of the
following terms and conditions has been satisfied:

                  (a)      The Administrative Agent shall have received duly
         executed counterparts of this Amendment signed by the Guarantor;

                  (b)      The continued truth and accuracy of the
         representations and warranties contained in Section 3 hereof; and

                  (c)      The Administrative Agent shall have received a fee of
         0.125% on the maximum principal amount guarantied under this Guaranty,
         which fee shall be fully earned as of the date hereof and
         non-refundable when paid.

         5.       Conditions Precedent to Effectiveness. This Amendment shall be
deemed effective as of the date (the "Effective Date") upon which each of the
following terms and conditions has been satisfied:


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                  (a)      The conditions set forth in Section 4 above shall
         have been satisfied;

                  (b)      The Administrative Agent shall have received a fee of
         0.125% on the maximum principal amount guarantied under this Guaranty
         (in addition to the fee required under Section 4(c) above), which fee
         shall be fully earned when due and non-refundable when paid;

                  (c)      The JS Industrial Packaging Group Acquisition shall
         have been consummated and the Security Agreement shall have been
         executed;

                  (d)      The Guarantor's requisite senior lenders shall have
         agreed to provisions amending the Guarantor Credit Agreement,
         substantially identical to the change in this Amendment to Section
         18(a)(i) of the Guaranty (and other senior lenders to the Guarantor
         similarly situated shall also have agreed to a substantially identical
         amendment), and such amendment shall have become effective; and

                  (e)      The Administrative Agent shall have received any
         other documents it may reasonably request, certified by an appropriate
         governmental official or officer of the Guarantor if so requested.

         6.       No Other Amendments or Waivers. Except for the amendments
expressly set forth and referred to in Sections 1 and 2, the Guaranty shall
remain unchanged and in full force and effect and is hereby in all respects
ratified and affirmed.

         7.       Counterparts. This Amendment may be executed in multiple
counterparts, each of which shall be deemed to be an original and all of which,
taken together, shall constitute one and the same agreement. In proving this
Amendment in any judicial proceeding, it shall not be necessary to produce or
account for more than one such counterpart signed by the party against whom such
enforcement is sought. Any signatures delivered by a party by facsimile
transmission shall be deemed an original signature hereto.

         8.       Governing Law. This Amendment shall be deemed to be made
pursuant to the internal laws of the State of New York with respect to
agreements made and to be performed wholly in the State of New York, and shall
be construed, interpreted, performed and enforced in accordance therewith.

         9.       Loan Document. This Amendment shall be deemed to be a Loan
Document for all purposes.



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                  IN WITNESS WHEREOF, the parties hereto have executed this
Amendment or caused it to be executed under seal by their duly authorized
officers, effective as of the day and year first written above.

GUARANTOR:                          CARAUSTAR INDUSTRIES, INC.

                                       By:
                                          ------------------------------------
                                       Its:
                                           -----------------------------------



ADMINISTRATIVE
AGENT:                              TORONTO DOMINION (TEXAS), INC.



                                       By:
                                          ------------------------------------
                                       Its:
                                           -----------------------------------


FIFTH AMENDMENT TO PARENT GUARANTY