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                                                                   Exhibit 10.18

                              AGREEMENT OF SUBLEASE

         This Agreement of Sublease ("Agreement") is made this 1st day of
December 1999, by and between XL Vision, Inc., a Delaware corporation,
("Sublessor"), and eMerge Interactive, Inc., a Delaware corporation,
("Sublessee").

                                   BACKGROUND

         A. By that certain Lease dated June 30, 1999 (the "Lease"), between XL
Realty, Inc. ("Landlord"), as landlord, and Sublessor, as tenant, Sublessor
leased from Landlord the premises consisting of approximately 63,000 square feet
(the "Premises") in the building (the "Building") located at 10315 102nd
Terrace, Sebastian, Florida, 32958, Indian River County (the "Property"), as
more particularly described in the Lease, at the rental and upon the terms and
conditions set forth in the Lease.

         B. Sublessor desires to sublease a portion of the Premises to
Sublessee, consisting of approximately 17,073 square feet of space of the
Premises, along with the parking area immediately adjoining the Building
("Subleased Premises"), upon the terms and conditions set forth herein.

         Capitalized terms used in this Agreement and not otherwise defined in
this Agreement shall have the meanings established the Lease.

         NOW, THEREFORE, in consideration of the covenants herein contained, the
parties hereto, intending to be legally bound hereby, do covenant and agree as
follows:

         1. Sublessor's Representations. In order to induce Sublessee to enter
into this Sublease, Sublessor represents and warrants to Sublessee that: (a) the
Lease comprises the entire understanding and agreement of Landlord and Sublessor
with respect to the Premises, (b) neither Landlord nor Sublessor is in default
under the Lease, and there exists no state of facts and no event has occurred
which, with the passage of time or the giving of notice, or both, would
constitute a default by either Landlord or Sublessor under the Lease, and (c)
the Premises are in good condition and repair and Sublessor is not aware of the
need to repair any part of the Premises.

         2. Sublease. Sublessor hereby leases to Sublessee, and Sublessee hereby
hires from Sublessor, the Subleased Premises for the period commencing December
1, 1999 ("Commencement Date") and ending on November 30, 2000 ("Expiration
Date") upon the terms and conditions set forth herein and at all times subject
to the Lease. Sublessee, for the benefit of Sublessor and Landlord, hereby
agrees that the Lease is incorporated herein by reference, and Sublessee agrees
further to be bound by all of the terms, covenants and conditions on the part of
"Tenant" to be done, performed and observed under the Lease with respect to the
Subleased Premises. Notwithstanding the Expiration Date established in the
preceding sentence, this
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Agreement shall, unless Landlord elects otherwise, terminate immediately upon
the termination or expiration of the Lease.

         3. Rent. Sublessee shall pay Sublessor an annual rental equal to $5.71
per square foot times the rentable area of the Subleased Premises, in equal
monthly installments of Eight Thousand One Hundred Twenty Four Dollars
($8,124.00), in advance, on the first day of each month during said term, at the
office of Sublessor or such other place as Sublessor may designate, without any
set off, counterclaim or deduction whatsoever, except that Sublessee shall pay
the first monthly installment, pro-rated for the partial month, if any, upon the
execution hereof.

         4. Operating Expenses. Sublessee's portion of the common area
maintenance charges and operating expenses charged by Landlord to the Sublessor
shall be 27.1% ("Sublessee's Share of the Premises"). The actual amount owed by
Sublessee shall be obtained by applying Sublessee's Share of the Premises to the
common area maintenance charges and operating expenses payable by Sublessor
under the Lease, and Sublessee shall pay the resulting amounts to the Sublessor
within ten (10) business days after the date that the Sublessor sends a bill
therefor to Sublessee. The bill will include a copy of the invoice or other
statement, if any, received from Landlord..

         5. Use. Sublessee shall use and occupy the Subleased Premises for
general office uses and as an industrial facility including design, engineering,
manufacturing, storage and distribution of Sublessee's products, and for no
other purposes.

         7. Services. Sublessee shall look solely to Sublessor for all services
to be rendered to Sublessee under the Lease as if Sublessee were "Tenant" and
Sublessor were "Landlord" under the terms of the Lease. Sublessor agrees to
perform all obligations of Landlord under the Lease for the benefit of
Sublessee. Landlord shall have no liability to Sublessee, and Sublessee agrees
that it shall have no rights against Landlord, by reason of this Agreement.

         8. Insurance.

                  (a) Notwithstanding anything herein to the contrary, to the
extent that either party is required by the provisions of this Agreement or the
Lease to carry insurance, each party hereto hereby releases the other party, its
directors, officers, agents, employee and servants to the extent of the
releasing party's actual recovery under its insurance policies, from any and all
liability or responsibility to it or anyone claiming by, through or under it or
them by way of subrogation or otherwise, for any loss or damage which may be
inflicted upon the property of such party, notwithstanding that such loss or
damage shall have arisen out of the negligent or intentionally tortious act or
omission of the other party, its agents or employees.

                  (b) Each insurance policy that either party is required or
authorized to carry hereunder shall contain a clause that the release provided
herein shall not affect the policy. Each
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insurance policy that either party is required to carry hereunder shall contain
a waiver of any right of subrogation against the other party. Sublessor and
Sublessee hereby waive any right of subrogation against each other on behalf of
any and all insurers providing insurance required by the terms hereof.

                  (c) Sublessee, at its sole expense, shall maintain for the
benefit of Sublessor and Landlord, such policies of insurance (and in such form)
as are required by the Lease with respect to the Subleased Premises, which
policies shall be reasonably satisfactory to Sublessor and Landlord as to
coverage and insurer. Each such policy shall name Sublessor and Landlord as
additional insured parties.

         9. Hold Harmless. Neither Sublessor nor Sublessee shall do or cause to
be done, or suffer or permit any act or thing to be done, which may cause the
Lease or the rights of Sublessor or Sublessee to be canceled, terminated,
forfeited or prejudiced or which may make the other party liable for any
damages, claims, fines, penalties, costs or expenses thereunder. Each of the
Sublessor and Sublessee shall indemnify and save harmless the other from all
suits, actions, judgments, damages, claims, liabilities, awards, losses, fines
penalties, costs, charges and expenses, including attorneys fees, that either
may sustain by reason of the other's failure to perform the terms of this
Agreement or the Lease or by reason of the breach by the other of any of the
terms, covenants or conditions of this Agreement or the Lease except those
arising out of the negligent acts or omissions of the party being indemnified.

         10. Defaults. The provisions of the Lease relating to defaults and
remedies are incorporated herein by reference as a separate paragraph of this
Agreement and, for purposes of determining the parties' defaults and remedies
hereunder, said provisions shall apply between Sublessor and Sublessee reading
"Landlord" to mean Sublessor and "Tenant" to mean Sublessee.

         11. Binding Effect. The provisions of this Agreement shall be binding
upon and inure to the benefit of the parties hereto and their respective legal
representatives, successors and assigns. This Agreement constitutes the entire
agreement between the parties hereto and may not be modified except by an
instrument in writing signed by the parties hereto.

         14. Notices. Whenever it shall be necessary or desirable for either
party to this Agreement to serve any notice or demand on the other party, such
notice or demand shall be served by certified mail, return receipt requested, or
by overnight courier (such as Federal Express), next day delivery. Each party
shall provide to the other copies of all notices received by each from Landlord.

         15. Amendments. No amendments shall be made to this Agreement without
the prior written approval of Landlord in accordance with the terms of the
Lease.

         16. Counterparts.  This Amendment may be executed in counterparts.
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         IN WITNESS WHEREOF, Sublessor and Sublessee have executed this
Agreement of Sublease as of the date first above written.

                                            SUBLESSOR:

                                            -----------------------------------


                                            By:
                                               --------------------------------
                                               Name:
                                               Title:

         (Corporate Seal)

                                            Attest:
                                                   ----------------------------
                                                   Name:
                                                   Title:

                                            SUBLESSEE:

                                            -----------------------------------


                                            By:
                                               --------------------------------
                                               Name:
                                               Title:

         (Corporate Seal)

                                            Attest:
                                                   ----------------------------
                                                   Name:
                                                   Title: