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                                                                   EXHIBIT 10.37

                              GUARANTY OF SUBLEASE

            GUARANTY by the undersigned, WEIGHT WATCHERS INTERNATIONAL, INC., a
Virginia corporation ("Guarantor"), annexed to that certain Agreement of
Sublease dated September ___, 2000 (the "Lease") between RDR ASSOCIATES, INC.
("Landlord"), as sublandlord, and WEIGHTWATCHERS.COM, INC. ("Tenant"), as
subtenant.

            In consideration of the simultaneous subletting of space on the 8th
floor of the building at 888 Seventh Avenue, New York, New York by Landlord to
Tenant (such premises being more particularly described in the Lease),
Guarantor, for itself and on behalf of its successor and permitted assigns,
hereby jointly and severally:

            1     Unconditionally guarantees to Landlord, its successors and
assigns, the full payment, performance and observance of all the terms,
covenants and conditions of the Lease therein expressed on Tenant's part to be
paid, performed and observed. If, at any time, Tenant shall default beyond any
applicable notice and cure period in the performance or observance of any of
such terms, covenants and conditions, Guarantor shall keep, perform and observe
the same, as the case may be, in the place and stead of Tenant. The foregoing
shall include any liability of Tenant which shall accrue under the Lease for any
period preceding, as well as any period following, the respective commencement
and expiration (or termination) dates of the Lease.

            2     Agrees that Guarantor's obligations hereunder shall exist
without requiring any notice (except as expressly provided for in the Lease) of
breach or default of or by Tenant to be delivered by Landlord to Guarantor, all
of which Guarantor hereby expressly waives.

            3     Agrees to and with Landlord, its successors and assigns, that
Guarantor, at Landlord's option, may be joined in any action against Tenant in
connection with the Lease, and that recovery may be had against Guarantor in
such action or in any independent action against Guarantor without Landlord
first pursuing or exhausting any remedy or claim against Tenant, its successors
or assigns. Guarantor also agrees that it will be conclusively bound by the
judgment in any such action to Landlord against Tenant (wherever brought)
whether or not it was a party to such action. Guarantor waives all right to
trial by jury in any action or proceeding hereinafter instituted by Landlord
concerning this Guaranty or the Lease to which Guarantor may be a party.

            4     Agrees that this Guaranty shall remain and continue in full
force and effect as to any renewal, extension or modification of the Lease
(including any holdover), and as to any assignment or subletting of the premises
demised under the Lease, but in case of any Lease modification, the liability of
Guarantor shall be deemed modified in accordance with the terms of any such
modification. In addition, any act of Landlord, its successor or assigns,
consisting of a waiver of any of the terms or conditions of the Lease, the
giving of any consent to any matter or thing relating to the Lease or the
granting of any indulgences or extensions of time to Tenant, may be done without
notice to Guarantor and without releasing any of its obligations hereunder.

            5     Agrees that the liability of Guarantor hereunder shall not be
affected by (a) the release or discharge of Tenant in any creditors',
receivership, bankruptcy or other proceedings, (b) the impairment, limitation or
modification of the liability of Tenant in

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bankruptcy, or of any remedy for the enforcement of Tenant's liability under the
Lease, resulting from the operation of any present or future provision of any
Bankruptcy Act or other statute or from the decision in any court, (c) the
rejection or disaffirmance of the Lease in any such proceedings, (d) the
assignment or transfer of the Lease by Tenant, (e) any disability or other
defense of Tenant (other than the defense that Tenant has complied with the
relevant obligation set forth in the Lease) or (f) the cessation from any cause
whatsoever of the liability of the Tenant.

            6     Warrants and represents that it has the legal right and
capacity to execute this Guaranty. In the event that this Guaranty shall be held
ineffective or unenforceable by any court of competent jurisdiction, then
Guarantor shall be deemed to be a tenant under the Lease with the same force and
effect as if it was expressly named as a joint tenant therein. This Guaranty
shall be governed by and construed under the laws of the State of New York.

            7.    Guarantor irrevocably consents and agrees that any legal
action or proceeding with respect to this Guaranty may be brought in any of the
Federal or state courts having subject matter jurisdiction located in the
Borough of Manhattan, The City of New York, and, by its execution and delivery
of this Guaranty hereby (a) accepts the non-exclusive jurisdiction of the
aforesaid courts, (b) irrevocably agrees that service of process to it out of
any of the aforesaid courts may be made by mailing same to its address for
notices set forth below, (c) irrevocably agrees to be bound by any final
judgment (after any appeal) of any such court with respect to this Guaranty, and
(d) irrevocably waives, to the fullest extent permitted by law, any objection
which it may now or hereafter have to the laying of venue of any suit, action or
proceeding with respect to this Guaranty brought in any such court, and further
irrevocably waives, to the fullest extent permitted by law, any claim that any
such suit, action or proceeding brought in any such court has been brought in an
inconvenient forum.

            IN WITNESS WHEREOF, Guarantor has executed this Guaranty as of this
12th day of September, 2000.

                              WEIGHT WATCHERS INTERNATIONAL, INC.

                              By: /s/ Thomas S. Kiritsis
                                  --------------------------------

                              Address For Notice:

                              Weight Watchers International, Inc.
                              175 Crossways Park West
                              Woodbury, N.Y.  11797
                              Attention:  General Counsel
                              Fax:  516-390-1795

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


            On the ____ day of September, 2000, before me, the undersigned,
personally appeared _____________________________________, personally known to
me or proved to me on the basis of satisfactory evidence to be the individual(s)
whose name(s) is (are) subscribed to the within instrument and acknowledged to
me that he/she/they executed the same in his/her/their capacity(ies), and that
by his/her/their signature(s) on the instrument, the individual(s), or the
person upon behalf of which the individual(s) acted, executed the instrument.



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                                                Notary Public