<PAGE>

Exhibit 10.15
Employment Agreement between LJL BioSystems, Inc. and Richard M. Eglen dated
February 4, 2000


                                February 4, 2000

Richard Malcolm Eglen
1410 Marinovich Way
Los Altos, CA 94024

Dear Richard:

         On behalf of LJL BioSystems, Inc. (the "Company"), I am pleased to
offer you the position of Sr. Vice President, Assay Technologies. Speaking
for myself, as well as the other members of the Company's management team, we
are all very impressed with your credentials and we look forward to your
future success in this position.

         The terms of your new position with the Company are as set forth below:

         1.       POSITION.

                  a. You will become a Sr. Vice President, Assay Technologies of
         the Company, working out of the Company's headquarters office in
         Sunnyvale, California. As a Sr. Vice President, you will have the
         overall responsibility for strategic direction and implementation of
         research and development, and growth of the reagent business, including
         creating and managing corporate collaborations and partnerships, as
         well as being a participant with the Company's executives in other
         areas of the business as required. You will report to the Company's
         Chief Executive Officer.

                  b. You agree to the best of your ability and experience that
         you will at all times loyally and conscientiously perform all of the
         duties and obligations required of and from you pursuant to the express
         and implicit terms hereof, and to the reasonable satisfaction of the
         Company. During the term of your employment, you further agree that you
         will devote all of your business time and attention to the business of
         the Company, the Company will be entitled to all of the benefits and
         profits arising from or incident to all such work services and advice,
         you will not render commercial or professional services of any nature
         to any person or organization, whether or not for compensation, without
         the prior written consent of the Company's Board of Directors, and you
         will not directly or indirectly engage or participate in any business
         that is competitive in any manner with the business of the Company.
         Nothing in this letter agreement will prevent you from accepting
         speaking or presentation engagements in exchange for honoraria or from
         serving on boards of charitable organizations, or from owning no more
         than one percent (1%) of the outstanding equity securities of a
         corporation whose stock is listed on a national stock exchange.

         2.       START DATE. Subject to fulfillment of any conditions
imposed by this letter agreement, you will commence this new position with
the Company on or before February 28, 2000 (which date of employment shall be
your "START DATE").

         3.       PROOF OF RIGHT TO WORK. For purposes of federal immigration
law, you will be required to provide to the Company documentary evidence of
your identity and eligibility for employment in the United States. Such
documentation must be provided to us within three (3) business days of your
Start Date, or our employment relationship with you may be terminated.

         4.       COMPENSATION.

                  a. BASE SALARY. You will be paid a monthly salary of
         $18,333.33, which is equivalent to $220,000.00 on an annualized basis.
         Your salary will be payable pursuant to the Company's regular payroll
         policy (or in the same manner as other officers of the Company).

                                      -27-
<PAGE>

                  b. ANNUAL REVIEW. Your base salary will be reviewed at the end
         of each calendar year as part of the Company's normal salary review
         process.

                  c. SIGNING BONUS. You will receive a signing bonus of
         $20,000.00 if you are employed with the Company 90 days after your
         Start Date.

         5        STOCK OPTIONS.

                  a. INITIAL GRANT. In connection with the commencement of your
         employment, the Company will recommend that the Board of Directors
         grant you an option to purchase 100,000 shares of the Company's Common
         Stock ("Initial Grant Shares") at the market price on the date of
         grant. The Initial Grant Shares will vest at the following rate: 20% of
         the total Initial Grant Shares shall vest on the first annual
         anniversary of the vesting commencement date (your Start Date) and
         1/20th of the total Initial Grant Shares shall vest on the quarterly
         anniversary of the vesting commencement date thereafter. Vesting will,
         of course, depend on your continued employment with the Company. The
         option will be an incentive stock option subject to the terms of the
         Company's 1997 Stock Plan and the Stock Option Agreement between you
         and the Company and limits under the tax code.

                  b. BONUS OPTION. In connection with the commencement of your
         employment, the Company will recommend that the Board of Directors
         grant you an additional option to purchase 50,000 shares of the
         Company's Common Stock ("Bonus Shares") at the market price on the date
         of grant. The Bonus Shares will vest on the five year anniversary of
         the vesting commencement date (your Start Date), PROVIDED THAT if you
         and your department meet certain performance milestones (to be mutually
         agreed on between the CEO and you) during your first twelve months of
         employment, up to 20% of the Bonus Shares shall vest on the annual
         anniversary of the vesting commencement date, and PROVIDED FURTHER that
         if you and your department meet certain performance milestones (to be
         mutually agreed on between the Chief Executive Officer and you each
         subsequent 12 month period of employment) during each subsequent twelve
         month period of employment, up to an additional 20% of the Bonus Shares
         shall vest on each such subsequent annual anniversary of the vesting
         commencement date, such that if the performance milestones for each
         year are fully met, the option to purchase Bonus Shares shall vest at
         an accelerated rate of 20% per annum on each annual anniversary of the
         vesting commencement date (full vesting in five years). Vesting will of
         course, depend on your continued employment with the Company. The
         option will be an incentive stock option subject to the terms of the
         Company's 1997 Stock Plan and the Stock Option Agreement between you
         and the Company and limits under the tax code.

                  c. SUBSEQUENT OPTION GRANTS. Subject to the discretion of the
         Company's Board of Directors, you may be eligible to receive additional
         grants of stock options or purchase rights from time to time in the
         future, on such terms and subject to such conditions as the Board of
         Directors shall determine as of the date of any such grant.

         6.       BENEFITS.

                  a. INSURANCE BENEFITS. The Company will provide you with its
         standard medical and dental insurance benefits, beginning on the first
         day of the month after the month in which your employment commences,
         with 100% of the premium paid by the Company. Dependent coverage will
         be offered at extra cost and partially paid for by you on a pretax
         basis. Long term disability insurance is included in the benefits
         package and is paid for by the Company. After you have been employed
         for three months with the Company, you will be eligible to participate
         in the Company's 401k retirement plan offered through Prudential
         Securities. In addition, the Company currently indemnifies all officers
         and directors to the maximum extent permitted by law, and you
         will be requested to enter into the Company's standard form of
         Indemnification Agreement giving you such protection. Pursuant to
         the Indemnification Agreement, the Company will agree to advance any
         expenses for which indemnification is available to the extent
         allowed by applicable law.

                  b. VACATION. You will be entitled to 10 days paid vacation per
         year, pro-rated for the remainder of this calendar year. After three
         years of employment with the Company, you will be entitled to 15 days
         paid vacation per year. After seven years of employment with the
         Company, you will be entitled to 20 days paid vacation per year. In
         addition, the Company provides a personal day off per year that could
         be taken with your vacation.


                                      -28-
<PAGE>


         7. PROPRIETARY INFORMATION AND INVENTIONS AGREEMENT. Your acceptance of
this offer and commencement of employment with the Company is contingent upon
the execution, and delivery to an officer of the Company, of the Company's
Proprietary Information and Inventions Agreement prior to or on your Start Date.

         8. AT-WILL EMPLOYMENT. Notwithstanding the Company's obligation
described in Section 9 below, your employment with the Company will be on an "at
will" basis, meaning that either you or the Company may terminate your
employment at any time for any reason or no reason, without further obligation
or liability.

         9. SEVERANCE AGREEMENT. In the event of a change in control of the
Company where your employment is terminated within a 12 month period of that
change (i) you will be entitled to receive continuation of your base salary for
up to twelve months following the date of termination of your employment (the
"Severance Period"), PROVIDED THAT if you commence full-time employment during
the Severance Period, the Company's obligation to pay any severance shall cease
at the time of such employment, and (ii) 20,000 shares of stock subject to your
unvested outstanding Initial Grant Shares shall immediately vest in full. For
purposes of this section, "full-time employment" shall be defined as at least 35
hours per week of compensated labor, including, but not limited to, consulting
or other contract work.

         10. CONTINGENCY. This offer is contingent on approval by the
Compensation Committee and the Board of Directors.

         We are all delighted to be able to extend you this offer and look
forward to working with you. To indicate your acceptance of the Company's offer,
please sign and date this letter in the space provided below and return it to
me, along with a signed and dated copy of the Proprietary Information and
Inventions Agreement. This letter and Proprietary Information and Inventions
Agreement set forth the terms of your employment with the Company and supersede
any prior representations or agreements, whether written or oral. This letter
may not be modified or amended except by a written agreement, signed by the
Company and by you. This offer shall expire at 5:00 PM on February 5, 2000, if
you have not delivered an acceptance to the Company before then.

                                                Very truly yours,

                                                LJL BIOSYSTEMS, INC.

                                                By: /s/ LEV J. LEYTES
                                                   ------------------
                                                Title: CEO
                                                       ---

ACCEPTED AND AGREED:

Richard Malcom Eglen

/s/ RICHARD M. EGLEN
--------------------
Signature

2/8/00
------
Date




                                     -29-