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                                                               EXHIBIT 10.15.2

                               AMENDMENT TO LEASE

1.       PARTIES.

         This Amendment dated as of May 28, 1996, is between Andover Mills
         Realty Limited Partnership ("Landlord") and PictureTel Corporation
         ("Tenant").

2.       RECITALS.

         2.1      Landlord and Tenant have entered into a Lease, dated February
                  10, 1994, as amended, for space at Brickstone Square in
                  Andover, Massachusetts (the "Lease"). Unless otherwise
                  defined, terms used in the Amendment have the same meanings as
                  those used in the Lease.

         2.2      Tenant wants to lease space on the fourth (4th) floor of the
                  Building (the "New Space"), which is depicted in Exhibit "BBB"
                  attached hereto and incorporated herein by this reference, and
                  is agreed to contain 29,979 square feet of rentable area. To
                  accomplish these and other matters, for Ten and NO/100 dollars
                  ($10.00) and other good valuable consideration, the receipt
                  and sufficiency of which is acknowledged, the parties agree
                  and the Lease is amended as follows, notwithstanding in the
                  Lease anything to the contrary:

3.       AMENDMENTS.

         3.1      "New Space Term" means the period starting on June 1, 1996,
                  and ending on the earliest of: June 30, 1999; the termination
                  of the Lease in accordance with its terms; or the termination
                  of the Lease with respect to the New Space in accordance with
                  the terms of this Amendment. Provided that all existing leases
                  of any portion of the New Space have terminated and all
                  existing tenants have vacated and surrendered possession of
                  those areas, Tenant may have access to the New Space before
                  the beginning of the "New Space Term" for the purpose of
                  performing Tenant Improvements. Beginning as of the date of
                  the first such entry by Tenant or its contractors or
                  personnel, all of the terms of the Lease will apply with
                  respect to the New Space and such entry and activities
                  thereon, except for Tenant's obligation to pay base rent,
                  Taxes and Operating Costs, which will begin as of the
                  beginning of the New Space Term as described below.

                  During the New Space Term: Tenant will lease, and the Premises
                  subject to the Lease will deemed to include, the New Space;
                  the base rent payable for the New Space will be $7.50 per
                  annum per square foot of agreed rentable area in the New Space
                  (i.e., $224,842.50 per annum), payable monthly in the same
                  manner and at the same times as the base rent for the rest of
                  the Premises; and Tenant will pay 3.19% of Taxes and Operating
                  Costs (and its pro rata share of Building Operating Costs
                  based on the rentable area of the New Space per Section 7.3 of
                  the Lease) allocable to the New Space Term without any
                  reference to or credit or 


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                  deduction for "Base Year Taxes" or "Base Year Operating
                  Costs," in addition to its share of Taxes and Operating Costs
                  for the rest of the Premises.

         3.2      Provided Tenant is not then in default (and has not committed
                  acts or omissions which with the giving of notice or the
                  passage to time would constitute a default), Tenant may
                  terminate the Lease with respect to the New Space effective as
                  of September 1, 1997, or October 1, 1997, or November 1, 1997,
                  in each case on at least four (4) months' prior written notice
                  to Landlord.

         3.3      On or before the termination date of the Lease with respect to
                  the New Space, Tenant will vacate and surrender the New Space,
                  remove all of its personal property, repair any damage caused
                  by Tenant to the New Space and return the New Space to a
                  condition at least as good as the condition it was in as of
                  the date hereof.

         3.4      Except as specifically set forth in this Section 3.4, Landlord
                  will not be required to pay for or perform any work to or for
                  the benefit of the New Space, and any required work and any
                  certificates of occupancy or other approval required for
                  occupancy of the New Space (if any) shall be Tenant's sole
                  responsibility and cost, and Tenant will indemnify, defend and
                  hold Landlord and its Affiliates harmless from all costs,
                  claims, liabilities and obligations (including, without
                  limitation, attorney's fees and costs) in connections with
                  obtaining or failing to obtain such certificates or other
                  approvals and for any acts or omissions by Tenant or its
                  contractors or subcontractors in connection with such work.
                  Within thirty (30) days after Tenant takes occupancy of the
                  New Space and pays its first month's rent for the New Space,
                  Landlord will pay to Tenant $29,979 as a tenant allowance for
                  work to be performed by Tenant in and for the New Space.

         3.5      The parties confirm that the Amendment between Tenant and
                  Landlord as of October 19, 1995, pursuant to which Tenant now
                  leases a portion of the New Space, was extended through May
                  31, 1996, when it will expire and be completely superseded by
                  this Amendment.

4.       NO OTHER CHANGES.

         The Lease is in full force and effect, and except as set forth above
         the Lease remains unchanged.


IN WITNESS WHEREOF, intending to be legally bound, the parties have executed
this Amendment under seal as of the date first set forth above.

                                          PICTURETEL CORPORATION

WITNESS: _____________________________        By: ______________________________
         Name Printed: Norman E. Gaut             Name: Lawrence M. Bornstein



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                                                  Title: Vice President
                                                  Authorized Signatory


                                          ANDOVER MILLS REALTY LIMITED
                                          PARTNERSHIP, a Massachusetts
                                          limited partnership

WITNESS: _____________________________        By: Niuna-Andover, Inc.,
         Name Printed: Carolyn Grover             a general partner

                                              By: ______________________________
                                                  Name: Martin Spagat
                                                  Title: Vice President
                                                  Authorized Signatory




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