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                                                                   EXHIBIT 10.18

                              CONSULTING AGREEMENT

     This Consulting Agreement (this "Agreement") is made by and between Aclara
BioSciences, Inc., a Delaware corporation (the "Company") and Dr. Eric Lander
(the "Consultant") as of January 15, 2000.

     1.   Services. During the term of this Agreement, the Consultant will
assist the Company in developing business and technical strategies for broadly
applying microfluidics technology to applications in chemical and biological
analysis. Company is aware of Consultant's primary employment with the Whitehead
MIT Center for Genome Research and this Agreement shall be subject to the
duties, obligations and restrictions resulting from Consultant's primary
employment.

     2.   Term. The services provided by the Consultant to the Company shall be
for the period January 15, 2000 until January 14, 2003 or until this Agreement
is terminated by either party in accordance with the provisions of Paragraph 7
hereof. The term shall be renewable upon mutual written agreement.

     The confidentiality commitments of the Consultant shall survive any
termination of this agreement and shall continue for a period of five (5) years
following the termination of this agreement.

     3.   Payment.

     Concurrently with execution of this CONSULTING AGREEMENT, Consultant is
granted an option to purchase Company shares in accordance with the Company
Option Plan as consideration for this CONSULTING AGREEMENT. The option shall
provide for the number of shares, the vesting preriod, the price, and the
conditions for exercising the option.

     The Company will reimburse the Consultant for reasonable travel expenses,
including fares, food and housing costs, incurred in connection with the
performance of consulting services under this Agreement requested by Company.
The Consultant will make every attempt to purchase coach class airfares when
traveling on behalf of the Company. Company shall promptly reimburse consultant
upon receiving invoices for such costs supported by documentation in support of
such invoices.

     The Consultant shall provide the Company with his/her full name, address,
and social security number.

     4.   Confidentiality.

          A.   The Consultant recognizes that in providing services under this
agreement he/she will have contact with information of substantial value to the
Company that is not generally known and that may, but need not, give the Company
an advantage over its competitors who do not know or use it, including, but not
limited to, techniques, designs, drawings, processes, inventions, developments,
equipment, prototypes, slides and customer, business and financial information,
relating to the business, products, practices or techniques of the Company. The
Consultant agrees to regard and preserve as confidential such confidential
information. The Consultant will not, at any time either during or after his/her
relationship with the Company (except as authorized by the Company for its
benefit), divulge or disclose, directly or indirectly, to any person, firm,
association or corporation other than bona fide employees of the Company or any
affiliate of the Company, acting in that capacity and have a need to know such
information, or use for his/her own benefit, gain or otherwise (i) any
confidential information, knowledge, or data concerning the business or affairs
of the Company or any affiliate of the Company, whether acquired by the
Consultant before, during, or after his/her relationship with the Company, or
(ii) any inventions, discoveries, improvements, products, processes, technology,
trade secrets, know-how, designs, formulas, or any other confidential material,
data, information or instructions, technical or otherwise, owned by the Company
or any affiliate of the Company, whether acquired before, during, or after the
Consultant's relationship with the Company, which, if disclosed, would adversely
affect the business of the Company or any of its affiliates or accord to a
competitor of the Company any competitive advantage. This Paragraph is not
intended to restrict the Consultant from disseminating or using any


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                   1288 Pear Avenue, Mountain View, CA 94034
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information which is published or available to the general public, except where
such publication or general availability is as a result of the Consultant's
acts. This duty of confidentiality does not apply to information which is or
becomes generally known to the public, through no act or omission of Consultant,
nor information provided Consultant by a third party without any restriction as
to use or disclosure.

          B.   The Consultant represents that his/her performance of the terms
of the Agreement does not and will not conflict with the terms of any agreement
to keep in confidence proprietary information and trade secrets acquired in
confidence or in trust prior to his/her advisory relationship with the Company.
The Consultant will not disclose to the Company, or induce the Company to use,
any confidential or proprietary information or material belonging to any third
party.

          C.   The Consultant represents that he/she is not knowingly presently
retained by any entity that designs, manufactures or sells products competitive
with those of the Company and he/she agrees not to accept such retention during
the term of this Agreement without prior written approval of the Company.
Accompanying this CONSULTING AGREEMENT is a list of the other consultant
relationhips that Consultant has.

     5.   Rights to Inventions and Discoveries.

          A.   The Consultant agrees that any inventions, discoveries,
improvements, processes, technology and know-how arising directly or indirectly
from the performance of advisory services under this Agreement that are based on
confidential information received from the Company and any patents issuing
thereon shall be the property of and are hereby assigned to the Company. The
Consultant further agrees that all original works of authorship which are made
by Consultant (solely or jointly with others) in the course of performance of
services under this Agreement and which are protectible by copyright are "works
made for hire," as that term is defined in the United States Copyright Act. In
order to permit the Company to claim rights to which it may be entitled under
this Paragraph 5 or applicable laws, and to insure that there is no conflict
with any business or activities of the Company, all inventions, discoveries,
improvements, processes, technology and know-how (whether or not patentable and
whether or not reduced to practice) and all works of authorship which the
Consultant may conceive or make (either by himself or jointly with others)
during the term of this Agreement with the Company (and during the six months
following the termination of this Agreement) and which relate to the field in
which advisory services are to be performed under this Agreement shall be
promptly disclosed to the Company in confidence unless precluded by Consultant's
full time employment.

          B.   Any invention, discovery, improvement, process, technology or
know-how which qualifies fully for protection under Section 2870 of the
California Labor Code is not subject to this Agreement. Any invention,
discovery, improvement, process, technology or know-how which does not qualify
fully for protection under said Section 2870 and which arises directly from the
performance of services under this Agreement shall be forthwith assigned to, and
shall be the sole property of, the Company.

          C.   Whenever requested by the Company, the Consultant shall execute
patent applications and copyright registrations and such other documents
considered necessary by the Company or its counsel to apply for and obtain
letters patents and copyright registrations in the United States, foreign
countries, or both, as the Company may deem advisable, or to otherwise protect
such inventions, discoveries, improvements, processes, technology, know-how or
works of authorship for the benefit of the Company coming within the Company's
rights as provided for in Section 5.A. The Consultant shall also make such
assignments and execute such other instruments as may be necessary to convey to
the Company the ownership and exclusive right in and to such inventions,
discoveries, processes, technology, know-how, patent applications, patents,
works of authorship or the like. The Company shall bear all of the expenses in
connection with the obtaining of such rights. The Consultant further agrees,
whether or not he/she is still providing services to the Company, to cooperate
to the extent and in the manner requested by the Company in the prosecution or
defense of any such patent or copyright claims or any litigation or other
proceeding involving any inventions, discoveries, improvements, processes,
technology, know-how or works of authorship covered by this Agreement in any
country of the world, but all time and expenses thereof shall be paid by the
Company. The foregoing covenant contemplates the inclusion of any improvements
of properties, rights, systems, inventions, works of authorship and the like
presently held by the Company or any affiliate thereof.


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                   1288 Pear Avenue, Mountain View, CA 94034
              (650) 210-1200, Fax: (650) 210-1210, www.aclara.com

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     6.   Independent Contractor Relationship. It is understood that the parties
hereto are independent contractors and engaged in the conduct of their own
respective businesses. Neither Consultant nor the Company is to be considered
the agent of the other for any purpose, and neither party has the right or
authority to enter into any contracts or assume obligations for the other or to
give any warranty or make any representation on behalf of the other, except
where and to the extent specifically authorized in writing to do so. Consultant
is not an employee of the Company and is not entitled to any of the benefits
provided by the Company to its employees.

     7.   Termination. This Agreement may be terminated at any time by mutual
consent. Termination shall not relieve the Consultant of its continuing
obligations under this Agreement, particularly the requirements of Paragraphs 4
and 5 above.

     8.   Miscellaneous.

          A.   This Agreement contains the entire agreement and understanding
regarding advisory services between the parties. There are no oral
understandings, terms or conditions and neither party has relied upon any
representation, express or implied, not contained in this Agreement.

          B.   All prior understandings, terms, or conditions regarding advisory
services are deemed merged in this Agreement. This Agreement cannot be changed
or supplemented orally but only in a writing signed by both parties. The
provisions of Paragraphs 4 and 5 shall survive the termination of this
Agreement. The terms and provisions of this Agreement shall be binding on and
inure to the benefit of the parties, their heirs, legal representatives,
successors and assigns.

          C.   Any notice or disclosures required to be given pursuant to this
Agreement shall be in writing and mailed to the parties at the addresses set
forth at the end of this Agreement.

          D.   This Agreement shall be governed by and constructed in accordance
with the laws of the State of California. The federal and state courts within
the State of California shall have exclusive jurisdiction to adjudicate any
dispute arising out of this Agreement. The parties consent to personal
jurisdiction of the federal and state courts within California and service of
process being effected by registered mail sent to the address set forth at the
end of this Agreement.

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first set forth above.

     ACLARA BIOSCIENCES, INC.               ERIC LANDER

By:
     ------------------------------------   ------------------------------------
     Joseph M. Limber                       Eric Lander, PhD
     Presient and CEO                       Director, Whitehead MIT Center
                                            for Genome Research

     Aclara BioSciences, Inc.               Whitehead MIT Center
     1288 Pear Avenue                       for Genome Research
     Mountain View, CA  94043               Cambridge, MA

        Consultant's Social Security Number:
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APPROVALS: CEO:                              FINANCE:
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                   1288 Pear Avenue, Mountain View, CA 94034
              (650) 210-1200, Fax: (650) 210-1210, www.aclara.com