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                                                                   Exhibit 10.17
                                    AGREEMENT


                  THIS AGREEMENT made this 16th day of April, 2001, by and
between MACKEN ASSOCIATES, a California Limited Partnership, (hereinafter
referred to as "Lessor") and DEPOSITION SCIENCES, INC., an Ohio Corporation
qualified to do business in the State of California, (hereinafter referred to as
"Lessee").
                                    RECITALS
                           The parties hereto previously entered into an
         Agreement dated March 2, 2001, (the "Lease") whereby Lessee would lease
         certain real property owned by Lessor commonly known as 3300 Coffey
         Lane, Santa Rosa, California, (the "Property") upon the satisfaction of
         certain conditions precedent, all of which were required to occur no
         later than March 16, 2001. All conditions were not satisfied on March
         16, 2001, and the Lease, by its terms, automatically terminated.
          The parties by this Agreement wish to provide for reinstatement of the
         Lease subject to certain modifications to the Lease as expressly stated
         herein and subject to the modifications to confirm and ratify all of
         the terms, covenants, and conditions of the Lease.

                                    AGREEMENT
                  NOW, THEREFORE, IT IS MUTUALLY AGREED AS FOLLOWS:

                  1. Section 1.1 of the Lease is hereby amended to read in its
entirety as follows:

         "1.1      This Agreement and this Amendment thereto shall become
                   effective when

                  (i) signed by all parties hereto upon the date of the party
         last signing,

                  (ii) upon receipt by the Lessee of executed Nondisturbance and

         Attornment Agreements as set forth in Paragraph 13.14 of this Lease
         [Lessor has deposited with the Escrow Holder hereinafter named the
         Nondisturbance and Attornment Agreements from Wells Fargo Bank and John
         Macken and provided copies to Lessee. Lessor has furnished Lessee
         copies of correspondence from Bay Area Development Corp., the holder of
         a second deed of trust against the Property


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         which Lessee has accepted as satisfying the requirements that Lessor
         executed Non-Disturbance and Attornment Agreement from said Bay Area
         Development Corporation],

                  (iii) upon confirmation of the lease guaranty contained in the
         Lease and execution of the lease guarantee provided with this amendment
         by Advanced Lighting Technologies, Inc. (hereinafter "ADLT"),

                  (iv) upon the submission into escrow of the Option Fee as
         provided for in the Option Agreement between the parties dated March 2,
         2001,

                   (v) John Macken and his affiliates shall have acquired 100%
         of the partnership interests of Lessor and all required consents to
         such acquisition have been obtained [Lessor has provided Lessee with
         documentation reflecting that John Macken now owns 80% of the
         partnership interests in Lessor. The documentation reflecting that
         Donald P. Macken has agreed to transfer the remaining 20% of the
         partnership interest to John Macken's nominees upon Donald P. Macken
         acquiring the remaining 20% interest from Ralph Skidmore, and the
         documentation reflecting that Donald P. Macken has entered into an
         agreement with Ralph Skidmore to acquire the remaining 20% interest
         subject to the approve of the U.S. Bankruptcy Court has been provided
         to Lessee],

                  (vi) John Macken shall have filed a notice of recission with
         respect to the notice of default recorded August 7, 2000, as instrument
         00-078996 regarding deeds of trusts filed as instrument numbers 1997
         0115820 and 1999 139354, Official Records of Sonoma County, California
         [Notices of Rescission of Notice of Default has been deposited with the
         Escrow Holder and a copy provided to Lessee],

                  (vii) Lessee shall have received satisfactory estoppel
         certificates from the holders of all deeds of trust filed against the
         Property, including among other things, a representation concerning the
         outstanding balance, default rate and existing defaults [Lessor has
         deposited an executed landlord waiver with Escrow Holder and provided a
         copy to Lessee. An estoppel certificate from Wells Fargo


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         Bank and John Macken has been deposited into escrow and copies
         furnished to Lessee. Lessor has furnished Lessee copies of
         correspondence from Bay Area Development Corp., the holder of a second
         deed of trust against the Property which Lessee has accepted as
         satisfying the requirements that Lessor provide an estoppel certificate
         from said Bay Area Development Corporation]; and

                  (viii) Lessee, at its expenses, shall have obtained a CLTA
         standard leasehold and option policy of title insurance subject only to
         (a) a lien to secure payment of real estate taxes and assessments, not
         delinquent; (b) the lien of supplemental taxes, not delinquent; (c)
         exceptions 4, 5, 6, 7, and 8 as set forth on Exhibit "C " hereto and
         (d) the standard printed exceptions with endorsement to delete the
         exclusions with respect to bankruptcy and creditor rights laws set
         forth as Item 6 in the Exclusions From Coverage. [Lessee has received a
         commitment from the Escrow Holder on behalf of Security Union Title
         Insurance Company to provide the foregoing policy of title insurance
         for the leasehold].

                  (ix) Lessee has received an acceptable legal opinion from Tom
         Kelley opining to the enforceability of the Lease and Option.

                  2. Sonoma Title Guarantee Co., 490 Mendocino Avenue, Santa
Rosa, California, 95401, is hereby designated by the parties as the Escrow
Holder and is hereinafter referred to as "Escrow Holder"). The duties of the
Escrow Holder shall be the same as set forth in the Escrow Agreement entered
into on March 2, 2001, by the parties hereto and Sonoma Title Guarantee Co.

                  3. The Lease, as modified herein, shall be effective
("Effective Date") as of the date all of the conditions provided for in Section
1.1 of the Lease are satisfied but in no event later than June 30, 2001.
Foregoing notwithstanding, Lessee may commence occupation of the Property on the
date hereof and Lessee's obligation to commence paying rent as provided in
Section 3.1 of the Lease shall commence on the date hereof but shall not be due
and payable until the date the U.S. Bankruptcy Court for the Northern District
of California approval of the sale and transfer of Ralph Skidmore's limited
partnership twenty percent (20%) interest in Lessor to Donald P. Macken.


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                  4. Except as herein otherwise expressly provided in this
modification, the parties hereby affirm and ratify all of the terms and
conditions of the Lease which shall commence as of the Effective Date as set
forth above.
                  IN WITNESS WHEREOF the parties hereto have executed this
Agreement as of the day and year first hereinabove written.

                                          MACKEN ASSOCIATES,
                                          A California Limited Partnership

                                          By /s/ John Macken
                                             -----------------------------------
                                                   General Partner

                                          DEPOSITION SCIENCES, INC.

                                          By /s/ Lee Bartolomei
                                            ------------------------------------


         The undersigned hereby agrees to guarantee the obligations of the
lessee hereunder.

                                  GUARANTOR:

                                  ADVANCED LIGHTING TECHNOLOGIES, INC.
                                  an Ohio Corporation


                                  By: /s/ Wayne R. Hellman CEO
                                     -------------------------------------------
                                                                      (Title)



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