EMPLOYMENT AGREEMENT


         This  AGREEMENT  made  effective  September  30,  1996  between  DIANON
SYSTEMS, INC., a Connecticut corporation, and any successor thereto, hereinafter
referred to as the "Company",  and DAVID  SCHREIBER,  residing at 1780 Nicholson
Drive, Hoffman Estates, Illinois 60192.

                                   WITNESSETH:

         WHEREAS,  the  Company  wishes  to  employ  David  Schreiber  and David
Schreiber  wishes  to  accept  such  employment,  in each  case on the terms and
subject to the conditions set forth below; and

         WHEREAS,  the services that David Schreiber  should render hereunder to
the Company are unique and valuable; and

         WHEREAS, the parties desire to reduce the terms and conditions of David
Schreiber's employment to writing;

         NOW,  THEREFORE,  in  consideration of the terms and conditions and the
mutual  covenants  contained in this Agreement,  the Company and David Schreiber
hereby agree as follows:

         1.  Employment
             ----------

             The Company hereby employs David Schreiber as of the first full day
of service he  provides to the  Company  hereunder  which shall be no later than
November 1, 1996 and David  Schreiber  hereby accepts such  employment  upon the
terms and conditions  hereinafter set forth. The parties  acknowledge that David
Schreiber's  employment  with the  Company is at will and  terminable  by either
party at any time for any reason.

         2.  Duties and Responsibilities
             ---------------------------

             David  Schreiber,  as  Chief  Financial  Officer  and  Senior  Vice
President,  Finance,  shall perform with continuous  diligence those  activities
assigned to David  Schreiber by the Company's  President or, in the absence of a
President, its Board of Directors. Commencing with the first full day of service
he provides to the Company  hereunder,  David Schreiber will be elected as Chief
Financial Officer and Senior Vice President, Finance, of the Company.


         3.  Term
             ----

             This  Agreement  shall  begin  on the  effective  date  hereof  and
continue until terminated under the terms contained herein.

         4.  Salary and Incentive Compensation
             ---------------------------------

             The Company  shall  compensate  David  Schreiber  for his  services
during the term of this Agreement  commencing with the first full day of service
he provides to the Company hereunder on a salaried basis paid in installments at
a rate  determined  by the Company from time to time,  provided that the initial
base salary  shall be at an  annualized  rate of $190,000.  Commencing  with the
first full day of service he provides to the Company hereunder,  David Schreiber
shall also  participate,  according to its terms,  in any  management  incentive
compensation  program maintained by the Company for salaried Grade 18 management
employees  of the  Company  during  the  term of this  Agreement.  A copy of the
Management Incentive Plan currently in effect is attached as Exhibit A.

         5.  Fringe Benefits
             ---------------

             During the term of this  Agreement,  commencing with the first full
day of service he provides to the Company  hereunder,  the Company shall provide
David  Schreiber  benefits and  emoluments as authorized  for all other salaried
Grade 18  management  employees of the Company as they may be modified from time
to time by the Company during the term of this Agreement,  including at the time
of execution of this Agreement,  health and medical  insurance,  life insurance,
sick leave, vacation, holidays, retirement plan participation and stock purchase
plan participation.  In addition, the Company shall provide David Schreiber with
a  Company-leased  automobile for his use and shall  reimburse him in accordance
with  Company  practice for business  related  fuel usage,  routine  maintenance
expenses, and auto insurance expense.

         6.  Stock Options
             -------------

             Upon  execution of this  Agreement,  the Company  shall award David
Schreiber  Incentive  Stock Options to purchase 50,000 shares of common stock of
the Company at the fair market value on said date, on term, conditions,  vesting
schedules and expiration dates which are  substantially  equivalent to the stock
option award document attached to this Agreement as Exhibit B.

         7.  Signing Bonus
             -------------

             Upon  execution  of this  Agreement,  David  Schreiber  shall earn,
payable upon his first day of employment, a signing bonus of $80,000 (subject to
appropriate withholding taxes) payable by the Company.


         8.  Stock Grants
             ------------

             Provided David  Schreiber's  employment with the Company  continues
through the date below without  notice of intent to terminate  having been given
by either  party,  the Company  shall issue to David  Schreiber  7,500 shares of
common stock of the Company on April 1, 1997. David Schreiber agrees not to sell
any such stock for a period of six months from the date of such grant.

         9.  Relocation
             ----------

             The Company shall pay for and reimburse  expenses  associated  with
David  Schreiber's  relocation  connected  with his hire in accordance  with the
Company's policy on Relocation and Moving Expenses,  a copy of which is attached
to this  Agreement  as Exhibit C;  provided  further  that,  the  Company  shall
compensate David Schreiber if his current res-idence is sold prior to January 1,
1997,  pursuant to said  policy's  guaranteed  home sale plan or otherwise in an
arms length  transaction,  at a price  insufficient  to  compensate  him for his
equity in the  residence at the time of sale,  including  the value of permanent
improvements  made by him (the  amount of which  equity  including  improvements
shall be  determined  by the Company on the basis of  appropriate  documentation
satisfactory to the Company to be supplied by David  Schreiber,  but which in no
event shall exceed $115,000). Any such equity compensation shall be subject to a
gross up  payment  for tax  purposes  as  described  in  Section  III(I)  of the
Company's policy on Relocation and Moving Expenses.

         10. Termination
             -----------  

             a)  This  Agreement   shall  terminate  on  any  of  the  following
occurrences:

                   (i) David Schreiber's death
                  (ii) David  Schreiber's  disability for a period of 90 days or
                       more unless waived by the Board of Directors;
                 (iii) mutual  agreement  of  the  parties  reduced  to  writing
                       signed by both parties;
                  (iv) voluntary resignation by David Schreiber
                   (v) termination by the Company without Stated Cause;
                  (vi) termination by the Company with Stated Cause.

             b) Cause shall mean David Schrieber's

                   (i) gross negligence
                  (ii) insubordination;

                 (iii) willful misconduct;

             c) "Stated Cause" shall mean Cause  communicated to David Schreiber
by the Company in a Notice of Termination.

             d) "Notice of  Termination"  shall mean written  notice given to by
either party to the other of an intention to terminate this  Agreement  pursuant
to subparagraphs (a) (iv), (v) or (vi) of this Paragraph of this Agreement.

             e) Notice  of  Termination  shall  be  sent by  certified  mail  or
registered mail, return receipt requested,  first class postage prepaid,  to the
residence in the case of David  Schreiber,  and to its  principal  office in the
Town of Stratford, Connecticut, to the attention of the President.

             f) The "Termination  Date" shall be the date David Schreiber ceases
providing services to the Company as an employee.

         11. Compensation after Termination
             ------------------------------

             a) David  Schreiber  will not  receive  any  compensation  from the
Company after the Termination Date other than accrued,  unused vacation,  except
as  described  under  Paragraph  (b) of  this  Section  of  this  Agreement,  if
applicable.  David Schreiber's  participa-tion in all fringe benefits offered by
the Company to its employees  will cease  immediately  on the  Termination  Date
except as  described in Paragraph  (b) of this  section of this  Agree-ment,  if
applicable. Nothing in this Agreement, however, is intended to impair any rights
vested under the law in any benefit plan in the Company.

             b) If this  Agreement  and David  Schreiber's  employment  with the
Company is  terminated  by the Company  without  Stated  Cause,  then during the
applicable  "Post  Termination  Period"  described in  subparagraph  (v) of this
paragraph:

                   (i) The Company will  pay David Schreiber at his rate of base
                       pay determined as of the  day  preceding the  Termination
                       Date.

                  (ii) David Schreiber shall act as a consultant to the Company
                       as requested by the Company for up to six days per month.

                 (iii) The Company  will contribute  towards the premium cost of
                       medical continuation  coverage for David Schreiber and/or
                       his  dependents on the same basis as it then  contributes
                       towards the medical  coverage of active  employees and/or
                       their  dependents,  for any months in said period  during
                       which David Schreiber  and/or his dependents are eligible
                       and elect to continue such coverage.




                  (iv) The  Company  will  pay up to  $10,000  for  outplacement
                       services for David Schreiber  provided by an outplacement
                       provider of David Schreiber's choice.

                   (v) If   termination   occurs   within   the  first  year  of
                       employment,  or at a later  time but  within  six  months
                       after the Company's  being  acquired by another  business
                       entity,  the "Post Termination  Period" shall be a period
                       of one year  beginning  with  the  Termination  Date.  If
                       termination  occurs after one year of employment has been
                       completed and absent an acquisition  of the Company,  the
                       "Post Termination Period" shall be a period of six months
                       beginning with the Termination Date.

         12. Company Property
             ----------------  

             On the  Termination  Date,  or at any earlier point in time after a
Notice of  Termination  is  received  when a request is made by the  Company for
same,  David  Schreiber  will  turn  over to the  Company  all  notes,  reports,
memoranda, books, records, chemicals, devices and documents, whether in written,
typewritten,  computerized  or any other  form,  which are in David  Schreiber's
possession or under his control,  whether prepared by him or others,  related to
the Company or relating to the business of the Company. At the conclusion of the
period  described in paragraph  (b) of Section 11 of this  Agreement,  or at any
earlier  point in time when a request  is made by the  Company  for same,  David
Schreiber shall also return to the Company any Company car, keys,  parking card,
credit card,  business cards or other materials  related to this employment with
the Company or the operation of the Company.

         13. Proprietary Information
             -----------------------

             David  Schreiber  hereby agrees to all the terms and  conditions of
the Agreement  regarding  confidential  Company  information  attached hereto as
Exhibit D and incorporated  herein and has executed a copy thereof  concurrently
with this Agreement.

         14  Non-Competition
             ---------------

             David  Schreiber  agrees that, to the fullest  extent  permitted by
law, for the period of one (1) year after his Termination  Date, David Schreiber
(a) will not solicit business on behalf of any entity in the clinical  chemistry
business,  which is performing or marketing  anatomic  pathology  services other
than  PAP  tests  ("Competing  Entity"),  (b)  will not  solicit  business  from
customers of the Company,  (c) will not solicit the  employ-ment  or services of
any of the employees of the Company,  and (d) will not,  directly or indirectly,
participate in the ownership,  management, operation or control of any Competing
Entity in the continental  United States other than  California,  Washington and
Oregon,  provided  that  nothing  in this  Paragraph  shall  prevent  investment
ownership of less than 5% of the shares of a publicly traded Competing Entity.


         15. Remedy for Breach
             -----------------  

             David Schreiber acknowledges:

                  a)   that he may be an officer of the  Company  and as such he
                       would  be  conversant  with,  and  have  access  to,  the
                       business affairs,  records, trade secrets,  customers and
                       customer  lists,  suppliers,   supplier  lists,  patents,
                       technical   know-how,   chemicals,   devices,   sales  or
                       distribution   agents  and   representatives,   sales  or
                       distri-bution  agents  and  representatives'  lists,  and
                       other  confidential  and  proprietary  information of the
                       Company; and

                  b)   that his compliance  with the covenants and agreements in
                       this  Agreement  is necessary to protect the goodwill and
                       other proprietary interests of the Company; and

                  c)   that a breach of his  covenants  and  agreements  in this
                       Agreement  will  result  in  continuing  and  irreparable
                       damage to the Company for which there will be no adequate
                       remedy at law.

             Both the parties  recognize  that the services to be rendered under
this Agreement by David Schreiber are special and unique and of an extraordinary
character,  and that in the event  there is a breach by David  Schreiber  of the
terms and  conditions of this Agreement to be performed by him, then the Company
shall be entitled,  if it so elects,  to institute and prosecute  proceedings in
any  court of  competent  jurisdiction  either  in law or in  equity,  to obtain
damages for any breach of this Agreement, or to enforce the specific performance
thereof  by David  Schreiber,  or to  enjoin  David  Schreiber  from  performing
services for any Competing Entity.  The parties further recognize and agree that
breach by David  Schreiber of his obligations  under  Sections,  12, 13 or 14 of
this Agreement shall relieve the Company of its obligations  under paragraph (b)
of Section 11 of this  Agreement  but that such relief  shall not be an adequate
remedy at law.

         16. David Schreiber's Representation
             --------------------------------  

             David Schreiber  warrants and represents that neither the execution
and  delivery  nor the  performance  of this  Agreement  by him  will in any way
violate,  or conflict with, any other  agreement by which he may be bound or any
duty or  obligation  to which he may be subject  and that he will take all steps
necessary to comply with the representation.

         17. Assignments
             -----------  

             The rights and  obligations of David Schreiber under this Agreement
shall be  assignable  to and  binding  upon the  successors  and  assigns of the
Company  including  any  corporation  organized  by the  Company to carry on the
business of the Company.


         18. Entire Agreement
             ----------------  

             This instrument  contains the entire  Agreement of the parties.  It
may not be changed orally,  but only by agreement in writing signed by the party
against  whom  enforcement  of any waiver,  change,  modification  extension  or
discharge is sought.  This  Agreement  supersedes  any verbal,  written or other
agreement(s)  or  understanding(s)  existing  between  David  Schreiber  and the
Company relating to his employment or the other matters covered herein.

         19. Severability
             ------------  

             If any  provision of this  Agreement  shall be held  invalid,  such
invalidity  shall not affect any other  provisions of this Agreement not held so
invalid,  and only such provisions shall to the full extent  consistent with the
law remain in full force and effect.

         20. Applicable Law
             --------------  

             This  Agreement  shall  be  governed  by the  laws of the  State of
Connecticut.

         IN WITNESS WHEREOF,  the parties have executed or caused to be executed
this Agreement.

                                            DIANON SYSTEMS, INC.


  September 30, 1996                        By: /s/ Kevin C. Johnson
- -----------------------                        ----------------------
Date                                           Kevin C. Johnson


    10/1/96                                 By: /s/ David Schreiber
- -----------------------                        ----------------------
Date                                           David Schreiber




                                                                     Exhibit A
                                                                     --------- 

                             "STRIVE FOR EXCELLENCE"
                            MANAGEMENT INCENTIVE PLAN

PRINCIPLES:
- ----------

     A.   Provides  financial  incentive  for achieving  above average  results,
          specific objectives and performance.

     B.   Relates  rewards to specific  goals within each  individual's  area of
          responsibility as well as "shared" goals.

     C.   Disproportional  rewards superior vs. average performance by including
          a "Jackpot" provision.

     D.   Emphasizes  profitability  as the primary  company  goal by creating a
          bonus "pool" based on achieving operating income.

     E.   Maximizes full company motivation by including all management levels.


FORMULA:
- -------
                     I                II             III
                Maximum Bonus      Group          Individual
     Salary  X  As % of Salary  X  Goal       X   Goal         =  Incentive
                                   Achvmt. %      Achvmt. %       Compensation

Unless the Jackpot is  achieved,  a manager  cannot earn more than the  "maximum
bonus"  per cent of  his/her  salary.  The fact that the group goal can go above
100%  allows for some  offset in the event a manager  does not  achieve  each of
his/her individual goals.

Employees are eligible for MIP and other incentive  compensation or bonuses only
if  they  are  actively  employed  through  and  including  the day  payment  is
distributed.

Management may alter, modify or cancel this program as deemed necessary.


Maximum Bonus as % of Salary




Grade                     Participation Timing         Max. Bonus as % of Salary
- -----                     --------------------         -------------------------

                                                            
19 President              From first work day                     40

18                        From first work day                     35

17 Vice Presidents        From first work day                     30

16                        Eligible after 90 days                  25

15 Managers               Eligible after 90 days                  20

14                        Eligible after 90 days                  15

13                        Eligible after 90 days                  10





                                                                     Exhibit B
                                                                     --------- 

                              DIANON SYSTEMS, INC.
                              200 Watson Boulevard
                          Stratford, Connecticut 06497

                                                         SO Grant No.

                               STOCK OPTION GRANT




                                                                  
Optionee:                 David R. Schreiber         Date of Grant:       October 1, 1996

Termination Date:         September 30, 2006         Total No. of Shares:          50,000

Exercise Price Per Share              $6.625



We are  pleased to inform you that the  Compensation  Committee  of the Board of
Directors of DIANON  Systems,  Inc.  (the  "Company"),  has today granted you an
option  pursuant to the  Company's  1991 Stock  Incentive  Plan (the  "Plan") to
purchase an  aggregate  number of shares  shown above of the Common Stock of the
Company on the following terms and conditions:

         1. The purchase  price per share of the shares of Common Stock  subject
to this option is $6.625 per share.

         2. This option shall  expire at the close of business on September  30,
2006. Subject to acceleration in the event of a Change of Control (as defined in
the Plan), you must remain in the employ of the Company or a Related Company (as
defined in the Plan) for two years from the date hereof  before you can exercise
any part of this  option.  Thereafter  this option will  become  exercisable  in
installments as follows:

             Percentage of Shares            Date of Earliest Exercise (Vesting)
             --------------------            -----------------------------------
                      40%                                  10/1/98
                      20%                                  10/1/99
                      20%                                  10/1/00
                      20%                                  10/1/01

         In the event of a Change of Control  this  option  shall  become  fully
exercisable and vested.

         3. This option is intended to qualify as an  "Incentive  Stock  Option"
within the provisions of Section 422 of the Internal Revenue Code.

         4. The option  price shall be payable by you at the time this option is
exercised,  (i) in cash or (ii) by  delivering  shares  of  Common  Stock of the
Company which you have owned for at least six months prior to such exercise,  or
a combination  of cash and such shares,  having an aggregate  value equal to the
aggregate  option  price of the  shares as to which  this  option  is  exercised
(basing the value of any such shares of Common Stock on the fair market value of
the Common  Stock on the date of  exercise).  No shares of Common Stock shall be
issued pursuant to exercise of this option until full payment  therefor has been
made.

           5.  This  option  may  be  exercised  only  by  you  and  may  not be
transferred except by will or the laws of descent and distribution. In the event
of your death,  your legal  representatives  may exercise  this option as to the
shares of Common Stock which were immediately  purchasable by you at the date of
death,  within  ninety  (90) days  following  the date of death (but in no event
later than September 30, 2006).


         6. If your employment with the Company  terminates  after reaching your
normal  retirement  date under the Company's  retirement  plan or for any reason
beyond your  control  other than your death,  your  option  privileges  shall be
limited to the shares of Common Stock which were immediately  purchasable by you
at the date of such  termination and such option  privileges shall expire unless
exercised  within ninety (90 days) days after the date of such  termination  and
prior to the close of business on September  30,  2006.  If your  employment  is
terminated for reasons within your control, including without limitation,  cause
and voluntary resignation, all rights under this option shall expire on the date
of such termination.

         7. Your option is granted in tandem with a Limited  Stock  Appreciation
Right ("LSAR") which may be exercised only within the 60-day period  following a
Change of Control (as defined in the Plan). This means that with respect to each
share under  option,  you may  exercise  either the option or the Limited  Stock
Appreciation   Right,   but  not  both.  Upon  exercise  of  the  Limited  Stock
Appreciation Right, you shall receive,  for each share with respect to which the
Limited Stock Appreciation  Right is exercised,  an amount equal in value to (I)
the fair market  value of a share of Common  Stock on the date of exercise  over
(ii) the exercise price of the related  option.  The Limited Stock  Appreciation
Right shall be payable solely in cash.  Such amount shall be paid within 30 days
of the exercise of the Limited Stock Appreciation Right.

         8. The  Company  has the right to delay the  exercise of your option if
listing  registration or qualification of the Common Stock is required under any
federal or state  securities  law or stock  exchange or similar rule and has not
been obtained.

         9.  Nothing  herein  shall  restrict  the right of the  Company  or any
Related Company to terminate your employment at any time, with or without cause,
or to withhold  required  amounts upon the exercise of your option or LSAR.  The
Company  shall have the right to require you to pay, or make other  arrangements
satisfactory  to the Committee to satisfy,  all tax  withholding  obligations in
connection with the exercise of your option or LSAR.

         10. This option is subject to all of the other  terms,  provisions  and
conditions  of the  Plan,  a copy of which has been  furnished  to you and other
copies of which may be obtained by you from the Company.


                                            Very truly yours,

                                            DIANON Systems, Inc.



                                            By:
                                               ------------------------------
                                               Kevin C. Johnson
                                               President

Date:
     ----------------------


- ---------------------------
(Signature)


- ---------------------------
 (Address)


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




                                                                     Exhibit C
                                                                     ---------
 
                         RELOCATION AND MOVING EXPENSES


I.   OBJECTIVE
     ---------     

       To define the conditions under, and the extent to which, the Company will
       pay for and reimburse  expenses  associated  with the relocation of newly
       hired and transferred employees.

II.  POLICY
     ------     

       A. The  decision  to  relocate  a newly  hired  or  transferred  employee
          requires the approval of the  department  Director/Vice  President and
          the Company's President.

       B. To facilitate  the  recruitment  and  reassignment  of employees,  the
          Company may provide payment of certain relocation  expenses consistent
          with the following criteria only if Section II A has been fulfilled.

          1.   The costs  associated with  relocations  under the policy require
               careful  consideration of the  cost/benefit  issues by management
               before such a relocation is initiated.

          2.   Provisions  of this  policy do not apply if the  employee  or new
               hire  relocates  less than 50 miles from  his/her  prior  primary
               residence.   Furthermore,   expenses  associated  with  only  the
               employee's or new hire's primary  residence will be considered as
               eligible for coverage.

          3.   The  coverages   provided  to  transferred   employees  are  more
               comprehensive   than  those  normally   provided  to  new  hires.
               Extension  of any  transferee  coverages  to new  hires  requires
               approval by the President or Chief Executive Officer.

          4.   Relocation benefits for employees  transferred for specified time
               periods  with planned  ending  dates are not included  under this
               policy.

          5.   Exceptions  to this policy must be approved by the  President  or
               Chief Executive Officer.

          6.   This company will  establish an expense limit on the  individuals
               total relocation costs.
This value will be approved in writing by the President.

III. PRACTICES
     ---------

       Generally  speaking,  relocation expenses will be capped. The cap will be
       directly  related  to  the  position  being  filled  and  established  in
       conjunction  with II. A. (above)  prior to extending a relocation  offer.
       The maximum allowance values are for company budgeting  purposes of these
       specific items,  and do not reflect nor are they intended to suggest that
       the  employee is  authorized  to commit or incur these  expenses  without
       satisfying Part Ia (above) for each part III section.


       The following  items will be paid for or reimbursed as described  herein.
       Coverages are summarized in Exhibit "A" to this policy and are contingent
       on Section II A.

A.   "House-Hunting" Trips -
     ----------------------

       The Company will  reimburse the employee the expenses  incurred for up to
       two,three-day trips to search for and select a new residence. Included as
       reimbursable  expenses are travel, hotel,  babysitter,  and meal expenses
       for the employee and spouse.

B.   Physical Move -
     -------------

       The Company will pay the cost of moving  furniture and household goods to
       the  new  location,   including  insurance,   packing,   unpacking,   and
       installation of major household appliances.  The carrier must be approved
       by the Company.

       Items paid for and not paid for under this policy are as follows:




          Covered                                Not Covered
          -------                                ----------- 
                                              
          One Automobile (Second car             Boats
          may be moved by the employee           Lumber
          at the reimbursable rate in            Trailers
          effect for employee's use of           Cleaning Services at either location
          his/her own automobile (see            Workshops outside the residence
          Policy D.3.)                           Pets not normally
          Furnishings and Clothing kept          Household Pets e.g., horses
          in the house



C.   Temporary Storage - (approval in advance)
     -----------------

       In cases  where  moves  from old to new  residence  cannot be  reasonably
       coordinated  to occur  directly,  arrangements  can be made for temporary
       storage of household goods for a period of no more than 60 days.

D.   Movement/Relocation of Family
     -----------------------------

       1. Transportation - (if applicable)  of  the employee  and his/her family
          to the new residence should be by the most reasonable and direct means
          available  such  as  family  automobile  or  economy-class   scheduled
          airliner. Meals in route are also expected to be reasonable in cost.

       2. Temporary  Living - If the new  residence is  not ready to receive the
          family,   the  Company  will  reimburse   temporary  living  expenses,
          including  medium  priced  hotel and  meals,  for a period of up to 14
          days.

E.   Temporary living - Employee Only at New Location -
     ------------------------------------------------

       When the employee takes up an assignment at the new location prior to the
       arrival of his/her family and/or before  his/her new permanent  residence
       is ready for  occupancy,  the Company  will  reimburse  the  employee for
       approved living  accommodations for a period of up to 90 days,  including
       lodging, breakfast and evening meals.

       During such time period,  the Company will pay for periodic trips home by
       the employee, the frequency depending on the travel costs involved.


F.   Duplicate Housing Expense -
     -------------------------

       If the  employee  occupies  his/her  new  residence  prior to the sale of
       his/her prior residence,  the Company will reimburse the monthly carrying
       charge on such prior residence to the following extent:

       1. Monthly  reimbursable  duplicate  expenses including interest charges,
          insurance,   property  taxes  and  reasonable  maintenance  costs  for
          utilities, grass cutting, etc.

       2. The maximum period for such reimbursement is limited to 90 days.

G.   Closing Costs -
     -------------

       1. Prior Residence (Grade 15 & Above)
          ---------------     

          The Company will pay for closing costs on the disposition of the prior
          residence  consistent  with practices in the geographic area regarding
          the type and amount of such expenses  normally assigned to the seller.
          Such closing costs can include, but are not limited to:

          a.  Lawyer's Fees (up to a maximum of 1% of the old mortgage)
          b.  Realtor's Fees
          c.  Termite Inspection
          d.  Points----(up to a maximum of 2)----Assigned to Seller
          e.  Mortgage Prepayment Penalty, Specified in the Mortgage
          f.  Title search
          g.  Recording Fees

Guaranteed  home sales  plan.  Employees  may elect to sell their  homes using a
"guaranteed sale plan". Through this plan, a relocation management firm retained
by the company will provide  employees  important  assistance in connection with
their home sales.  All fees charged by the relocation firm for its services will
be assumed by the company subject to the relocation cap.

The  relocation  management  firm will make a purchase  offer valid for 60 days.
This offer is based on the  appraised  fair market value (FMV) of the  employees
home.  The FMV of the  property  will be based on the average of the  appraisals
performed by the relocation firm. If required,  the employee can request another
appraisal firm, agreeable to both the company and the employee. The company will
assume the cost of the appraisals.

During the 60 day period,  if the employee is able to sell his or her house at a
higher  price than  appraised,  he or she may assign the sale to the  relocation
management  firm and receive  equity based on the higher price.  If the employee
sells the home to the  relocation  firm, he or she will receive  equity based on
the offer price (determined by the appraisals previously discussed).

If the employee  assigns an offer to the relocation  management firm, as soon as
any  contingencies  contained in the  assigned  sale  contract are removed,  the
employee will receive full equity based on the amended or higher sale price. The
firm  will  then  assume  all the  responsibilities  of the  employee-homeowner,
including sale closing.  If the sale  subsequently  falls through,  the employee
retains  full  equity  - and  the  property  remains  in the  relocation  firm's
inventory for resale.

If the property is purchased with an assumable  mortgage,  the  relocation  firm
will  indemnify  and hold  harmless the employee from any claim or loss due to a
valid  deficiency  judgment  against  the  employee  that may  arise  out of the
continuing liability under such mortgage. The indemnification  remains in effect
for the life of the loan, notwithstanding subsequent resales by property owners.


By selling or assigning a sale to the  relocation  firm,  the employee  receives
equity  when he or she  needs it (to  apply to a new  home  purchase  in the new
location) and avoids paying additional income taxes on reimbursed expenses.

       2. New Residence -
          -------------

          The Company  will also  directly  reimburse  the  employee for closing
          costs  normally  borne by the purchaser  when  purchasing  his/her new
          primary residence. Such closing costs can include, but are not limited
          to:

           a.  Title Search
           b.  Lawyer's Fees (up to a maximum of 1% of the new mortgage)
           c.  Points (up to a maximum of 2)
           d.  Inspections
           e.  Appraisals
           f.  Application Fee
           g.  Recording fee
           h.  State and local transfer taxes

H.   Termination of Lease at Prior Residence -
     ---------------------------------------

       If the  employee  resided  in a leased  or rented  property  prior to the
       transfer and must terminate or "break" the lease, the Company expects the
       employee  to  negotiate  a  reasonable   arrangement  with  the  landlord
       acceptable  to the Company,  at which point the Company will agree to pay
       the cost of any lease termination/breaking.

I.   Gross-up Payment for Tax Purposes -
     ---------------------------------
  
       Under  Federal  and State  tax laws in  existence  at the  time,  certain
       reimbursements  and payments  made to the employee or on his behalf under
       this policy may be considered taxable income.

       Deductible  and  non-deductible  moving  expense  reimbursements  will be
       included in an  employee's  taxable  income  under the category of "other
       earnings". Deductible expenses must be deducted from an employee's income
       when filing a federal tax return.  Non-deductible  expenses will be taxed
       as normal income.  Since  expenses vary from employee to employee,  these
       payments will be handled on an individual basis.

J.     General  Rule - Relocation  costs  are generally  capped by the  Company.
       Cumulative  expenses  shall  not  exceed  this  cap,  regardless  of  the
       individuals  requirements  and  costs  that  may be  associated  with any
       specific expense item.



                                    Exhibit A
                             -- Maximum Allowance --




    SUMMARY of COVERAGES              TRANSFEREES               NEW HIRES
    --------------------              -----------               --------- 
                                                          
    House-Hunting Trips              $500 Expenses           $500 Expenses
    - Up to Two Trips                $1,500 Air Fare         $1,500 Air Fare
    (three days each)

    Move Household Goods             $1,500 in State         $0 In State
    - (See Limits in Policy)         $6,000 out of State     $6,000 Out of State

    Temporary Storage                $500    (a)
    Up to 60 Days                    $2,500  (b)             $2,500   (b)
    (Need approval in advance)

    Transportation of Employee &     $250  Expenses          $250  Expenses
    Family  (See Limits in Policy)   $1,500 Air Fare         $1,500 Air Fare

    Temporary Living                 $1,500                  $1,500   (b)
    - Up to 14 Days

    Temporary Living
    (Employee Only)                  $6,800                  $6,800
    - Up to 90 Days

    Duplicate Housing                $3,500  (a)
    - Up to 90 Days                  $7,500  (b)             $7,500   (b)

    Closing Costs-Prior Residence    $15,000 (a)
    - (See Limits in Policy)         $20,000 (b)             $20,000 (b)

    Closing Costs-New Residence      $10,000 (a)             $10,000 (a)
    - (See Limits in Policy)         $15,000 (b)             $15,000 (b)

    Terminating Lease                $2,000                  $2,000  (b)
    - (See Limits in Policy)

    Gross-Up Payments-Estimated      $15,000 (a)             $15,000 (a)
    - (See Limits in Policy)         $25,000 (b)             $25,000 (b)

(a) Up to Grade 15                   (b) Grade 15 & above

    Probable Costs:
    Up to Grade 15:                  $58,000 $45,000
    Grade 15 and Above:              $80,000 $80,000



III. PRACTICES
     ---------

       Generally  speaking,  relocation expenses will be capped. The cap will be
       directly  related  to  the  position  being  filled  and  established  in
       conjunction  with II. A. (above)  prior to extending a relocation  offer.
       The maximum allowance values are for company budgeting  purposes of these
       specific items,  and do not reflect nor are they intended to suggest that
       the  employee is  authorized  to commit or incur these  expenses  without
       satisfying Part Ia (above) for each part III section.


       The following  items will be paid for or reimbursed as described  herein.
       Coverages are summarized in Exhibit "A" to this policy and are contingent
       on Section II A.




     SUMMARY of COVERAGES                TRANSFEREES               NEW HIRES
                                                                
     House-Hunting Trips
     - Up to Two Trips                        X                        X
      (three days each)

     Move Household Goods
     - (See Limits in Policy)                 X                        X


     Temporary Storage
     - Up to 60 Days                          X                 Grade 15 & Above


     Transportation of Employee & Family
     - (See Limits in Policy)                 X                        X


     Temporary Living
     - Up to 14 Days                          X                        X

     Temporary Living  (Employee Only)
     - Up to 90 Days                          X                        X

     Duplicate Housing
     - Up to 90 Days                          X                 Grade 15 & Above

     Closing Costs - Prior Residence
     - (See Limits in Policy)                 X                 Grade 15 & Above

     Closing Costs -  New Residence
     - (See Limits in Policy)                 X                        X

     Terminating Lease
     - (See Limits in Policy)                 X                 Grade 15 & Above

     Gross-Up Payments
     - (See Limits in Policy)                 X                        X





                                                                     Exhibit D
                                                                     --------- 


                                    AGREEMENT
                                    ---------

         THIS  AGREEMENT,  made  this  October  1,  1996 by and  between  DIANON
SYSTEMS,   INC.,   its   affiliates,   subsidiaries,   successors   and  assigns
(collectively  called hereinafter  "DIANON") and David Schreiber,  an individual
residing at 1780 Nicholson Drive,  Hoffman Estates,  Illinois 60192 (hereinafter
called "Employee").

         In  consideration  of the  commencement  of Employee's  employment with
DIANON, the payment of compensation and benefits for such employment, and access
to sensitive information,  Employee and DIANON acknowledge,  represent and agree
to the terms and conditions set forth in this Agreement.

         1.  Employee's  employment  with DIANON creates a relationship of trust
and  confidence  between the parties.  Employee  agrees  that,  during and after
his/her  employment  with DIANON,  Employee  will not use or disclose,  or allow
anyone else to use or disclose,  any  confidential  information  relating to the
products, sales and/or business affairs of DIANON or of any customer or supplier
of DIANON,  or any  information  created,  discovered,  or  developed  by or for
DIANON, or acquired by DIANON,  that has commercial value in DIANON's present or
future business ("Confidential Information"),  except as may be necessary in the
performance  of  Employee's  employment  with DIANON or as may be  authorized in
advance by  appropriate  officials of DIANON.  By way of  illustration,  but not
limitation,   Confidential  Information  includes  processes,   formulas,  data,
know-how, inventions,  improvements,  techniques, marketing plans, product plan,
strategies,  forecasts,  customer lists and any other  information  Employee has
reason to know  DIANON  would  like to treat as  confidential  for any  purpose.
Employee  agrees to keep  Confidential  Information  secret  whether  or not any
document containing such information is marked confidential.

         2. All rights, title and interest in all records,  documents,  or files
concerning the business of DIANON,  including,  but not limited to biomaterials,
processes,  letters,  trade  secrets,  laboratory  notebooks or other written or
electronically recorded material, whether or not produced by the Employee, shall
be and remain the  property  of DIANON.  Upon  termination  of  employment,  the
Employee shall not have the right to remove any such records from the offices of
DIANON. In addition,  Employee agrees to promptly return to DIANON all things of
whatsoever  nature that belong to DIANON,  and all records (in whatsoever  form,
format or medium) contained or related to Confidential Information of DIANON.

         3. Employee agrees to assign,  and does hereby assign to DIANON, all of
his/her  right,  title  and  interest  in and to all  inventions,  improvements,
discoveries or technical developments,  whether or not patentable,  which he/she
solely or jointly  with others,  may  conceive or reduce to practice  during the
term of his/her  employment (a) which are related in whole or in part,  directly
or indirectly,  to DIANON's product line, research and development,  or field of
technological or industrial specialization,  or (b) in the course of utilization
by DIANON of Employee's services in a technical or professional  capacity in the
areas  of  research,   development,   marketing,   management,   engineering  or
manufacturing,  or (c)  pursuant  to any  project of which  Employee is or was a


participant or member that is or was either  financed or directed by DIANON,  or
(d) at DIANON's expense, in whole or in part.

         4. Employee  agrees to disclose  promptly to DIANON's  President or his
designee, all ideas,  discoveries,  and improvements conceived by Employee alone
or in collaboration with others, and to cooperate fully with DIANON, both during
and after  employment,  with  respect  to the  procurement  of  patents  for the
establishment and maintenance of DIANON's or its designee's rights and interests
in said invention,  improvement,  discoveries or  developments,  and to sign all
papers which DIANON may deem  necessary or desirable  for the purpose of vesting
DIANON or its  designees  with such rights,  the expenses  thereof to be paid by
DIANON.

         5. The Employee  shall,  while employed by DIANON,  devote his/her best
efforts and his/her full time to the business of DIANON.

         6. In the event of a breach or threatened  breach of the  provisions in
this  Agreement,  DIANON  shall be entitled to an  injunction  restraining  such
breach,  it being  recognized  that any injury  arising  from a breach  would be
irreparable  and could have no adequate  remedy at law; but nothing herein shall
be construed as prohibiting  DIANON from pursuing any other remedy available for
such  breach or  threatened  breach.  In the event  that  Employee  breaches  or
threatens  a breach of this  Agreement,  DIANON  shall be  entitled  to have its
reasonable  legal fees and costs  paid by the  Employee  for any legal  services
relating to the breach or threatened breach.

         7. This  Agreement is not intended,  and should not be construed in any
way, as a contract of  employment  for a definite  period of time or to limit or
restrain   DIANON's  or  the  Employee's   right  to  terminate  the  employment
relationship at any time.

         8. In the  event  any  provision  or  paragraph  of this  Agreement  is
declared to be invalid or unenfoceable, then the balance of this Agreement shall
remain in full force and effect.

         9. This  Agreement  shall be construed and enforced in accordance  with
the laws of the State of Connecticut.

         10. The  foregoing  contains the entire  Agreement  between the parties
pertaining to confidential  DIANON  documents and  information.  No modification
thereof shall be binding upon the parties unless the same is in a writing signed
by the  respective  parties.  This Agreement and all of the terms and conditions
contained  herein  shall  remain in full force  during the period of  employment
notwithstanding any changes in compensation.

         11.  Employee   represents  and  warrants  that  he/she  has  no  other
agreements or  commitments  that would hinder or prevent  performance of his/her
job  responsibilities  with DIANON.  Unless authorized to do so, Employee agrees
not to disclose to DIANON or use in his/her employment with DIANON any invention
or  confidential  information  belonging to any former  employer or to any other
person other than DIANON.


         IN WITNESS WHEREOF,  the parties have entered into this Agreement as of
the date set forth below.


Employee:                                   DIANON SYSTEMS, INC.


/s/ David Schreiber                         By: /s/ Kevin C. Johnson
- -------------------                             ------------------------
David Schreiber                                 Kevin C. Johnson

Dated: 10/1/96                              Dated: September 30, 1996
       -------                                     ---------------------