Exhibit 10.4
                             EMPLOYMENT AGREEMENT


      This  Employment  Agreement  dated as of the 1st day of May,  1997 between
Bio-Reference  Laboratories,  Inc., a New Jersey  corporation with its principal
place of business at 481 Edward H. Ross Drive,  Elmwood  Park,  New Jersey 07407
(the  "Company")  and Sam Singer,  residing at 10 Heritage  Drive,  Edison,  New
Jersey 08820 (the "Employee").
                             W I T N E S S E T H :
      WHEREAS, the Company is primarily engaged in the operation of
a clinical laboratory in northern New Jersey, and
      WHEREAS,  the Company desires to avail itself of the Employee's  knowledge
and  experience  and to employ  the  Employee  as its Vice  President  and Chief
Financial Officer on the terms and conditions hereinafter set forth, and
      WHEREAS,  the  Employee  desires to be so  employed  by the Company on the
terms and conditions hereinafter set forth.
      NOW, THEREFORE, in consideration of the mutual covenants herein contained,
the parties agree as follows:
      1. Terms of  Employment.  The Company agrees to employ the Employee as its
Vice  President  and Chief  Financial  Officer,  or in such  other  position  of
comparable status and responsibility as the Company may from time to time direct
and/or  desire,  and the  Employee  agrees to accept  such  employment  with the
Company,  for a term commencing as of May 1, 1997 (the "Commencement  Date") and
continuing  until  October  31,  2002 (the  "Expiration  Date"),  unless  sooner
terminated as provided in this Agreement (the "Employment


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Period").  As used in this Agreement,  the term  "Employment  Period" shall also
include any periods for which this  Agreement  is renewed  pursuant to Section 2
hereof.
      2. Renewal. This Agreement shall be automatically renewable for additional
one year  periods;  provided,  that either the Company or the Employee may elect
not to renew this  Agreement upon written notice to the other party no less than
one (1) month before the  Expiration  Date or any subsequent  extension  thereof
pursuant to this Section 2.
      3.    Duties.
            ------
            (a) During the  Employment  Period,  the Employee shall perform such
duties and exercise such powers relating to the Company as are commensurate with
the office of Vice  President  and Chief  Financial  Officer and shall have such
other duties and powers as the Board of Directors shall from time to time assign
to him,  including by way of example but not limitation,  duties with respect to
any of the Company's associated companies.  As used in this Agreement,  the term
"Associated  Companies"  shall mean any company (i) of which not less than fifty
(50%)  percent of the equity is  beneficially  owned by the  Company or (ii) any
subsidiary of such company, if any.
            (b) During the Employment  Period,  the Employee shall devote all of
his working time during normal  business  hours and his best efforts and ability
to the business of the Company,  shall  faithfully  and  diligently  perform the
duties of his employment with

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the Company and shall do all reasonably in his power to promote,
develop and extend the business of the Company.
            (c) During the Employment  period, the Employee shall not, except as
a representative  of the Company or with the written consent of the Company,  be
directly or  indirectly  engaged,  concerned or interested in the conduct of any
other business competing or likely to compete with the Company;  provided,  that
notwithstanding  anything  contained  in this  Agreement  to the  contrary,  the
Employee  shall not be precluded  from devoting a reasonable  amount of his time
to:
            (i)  serving  with the prior  written  approval  of the Company as a
            director or member of a committee of any  organization  involving no
            conflict of interest with the business of the Company; and

            (ii)  managing  his  personal  investments;   provided,   that  such
            activities  shall  not  materially  interfere  with  the  Employee's
            performance of his duties hereunder.

            (d) The  Employee  shall be  employed  at the offices of the Company
located in Elmwood Park, New Jersey; provided that the Employee acknowledges and
agrees that the proper  performance  of these  duties may make it  necessary  to
spend reasonable periods of time in other parts of the country.


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      4.    Compensation.
            (a) During the Employment Period, the Company shall pay the Employee
as  compensation  for  his  services  under  this  Agreement,   a  minimum  Base
Compensation  at an annual  rate of One Hundred  Ninety  Thousand  Five  Hundred
($190,500)  Dollars  through  October 31, 1997,  and thereafter a minimum annual
Base Compensation  consisting of salary and bonus in the aggregate amount of Two
Hundred Twenty Thousand ($220,000) Dollars (the "Base  Compensation").  The Base
Compensation  shall be  payable in equal  installments  in  accordance  with the
regular payroll procedures established by the Company. In October of each fiscal
year  during the  Employment  Period,  the  Company's  Board of  Directors  will
consider increasing the Employee's Compensation under this Agreement, based upon
the  performance of the Company and of the Employee  during the fiscal year then
ending with such  increase,  if  granted,  taking  effect as of the  immediately
following November 1.
            (b) The  Company  shall pay for  (excluding  the P.S.  58 costs) and
maintain  "Split  Dollar"  Life  Insurance  in the face  amount of Four  Hundred
Thousand ($400,000) Dollars,  insuring the life of the Employee. The proceeds of
such  insurance  shall be  payable  to the  estate  of the  Employee  (excluding
benefits  required to be paid to the Company  pursuant to the split  dollar plan
for the premiums  paid).  Once such  insurance  is fully paid,  the Company will
apply for an additional  aggregate Four Hundred Thousand  ($400,000)  Dollars of
similar "Split Dollar" Life Insurance

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insuring the Employee's life and will maintain such additional  insurance during
his employment by the Company.
            (c) The Company shall lease and insure,  under the Company's policy,
an automobile for the benefit of the Employee.  The Company shall be responsible
for  maintenance,  gasoline,  repair  and all other  such  costs but only to the
extent such expenses relate to business use of the automobile. At the end of the
lease term, or in the event of the termination of this Agreement for any reason,
including non-renewal, the Employee shall have the following options:
            (i) surrender the automobile to the Company,
            (ii) assume the Company's lease payment obligation; or
            (iii) exercise the purchase option of the lease, if any.
            (d)   The Company shall promptly pay or reimburse the
Employee for all expenses  incurred by the  Employee in the  performance  of his
duties under this  Agreement.  Such expenses  shall be limited to the reasonable
out-of-pocket  expenses necessarily and actually incurred by the Employee in the
performance of his duties;  provided that (i) the expenses have been detailed on
a form  acceptable  to the Company and  submitted  to the Company for review and
approval and (ii) appropriate  supporting  documentation  is submitted  together
with the approved expense form.
            (e) The  Employee  shall be  entitled to  participate  in any fringe
benefit and bonus plans  available to the Company's  employees as in effect from
time to time, to the extent that the Employee may be eligible to do so under the
applicable provisions of the plans

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including but not limited to pension,  profit sharing,  stock option and similar
plans and life and medical insurance plans or coverage maintained by the Company
for senior personnel and/or all personnel.
            (f) The Employee shall be entitled to such  vacation,  personal time
and holidays as he is eligible for under the Company's  Employment and Personnel
Policy as the same presently exists or may hereinafter be amended.
            (g)  Notwithstanding  the  provisions  of  subparagraph  (a) of this
Section 4, the Employee  shall also be entitled to a percentage  increase in his
Base Compensation as in effect on June 30 of each year that this Agreement is in
effect, equal to the percentage increase in the Consumer Price Index - All Items
for the New York  metropolitan  area (or any successor  index) for such month of
June as  compared  to such  Consumer  Price  Index  for the month of June in the
immediately  preceding  year.  Any  such  increase  shall  be  effective  on the
immediately  following November 1. No adjustments shall be made for decreases in
such Index.
      5.    Issuances of Stock and Options. In further consideration
            ------------------------------
for his employment, the Company agreed on May 13, 1997 to the
following issuances of its Common Stock and options to the
Employee.
            (a)  Forfeitable  Stock -- The Company has issued  200,000 shares of
its Common  Stock to the  Employee  subject  to  forefiture.  If the  Employee's
employment  agreement  is  terminated  by  the  Company  "For  Cause"  or at the
Employee's option, without "Good Reason" (but

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not due to a "Change in Control"), all as herein defined, the
Employee will forfeit such shares on the following basis.
If Termination "For
Cause" or "Without Good
Reason" Occurs during the                            Number of Shares
   Following Periods                                     Forfeited
-------------------------                             ------------

May 1, 1997 through April 30, 1998                    150,000 shs.
May 1, 1998 through April 30, 1999                    100,000 shs.
May 1, 1999 through April 30, 2000                     50,000 shs.
            (b) Stock Options -- The Company has issued ten-year incentive stock
options  ("ISOs")to the Employee  exercisable  to purchase  50,000 shares of its
Common  Stock at  $.71875  per share.  These  ISOs are  subject to the terms and
conditions of the Company's 1989 Employees' Stock Option Plan.
      6. Disability. If during the Employment Period, the Employee shall incur a
Total Disability then,  subject to the earlier  termination of this Agreement or
the earlier  termination  of the  disability,  the Company shall  compensate the
Employee as provided in subparagraphs (a), (b), (c) and (d) of this Section 6.
            (a) For the month in which the Employee incurs the total disability,
and for the following  twelve (12) months of the  disability,  the Company shall
compensate the Employee at a rate equal to his then current Base Compensation.
            (b) For a period of three (3) months commencing upon the termination
of the period described in subparagraph  (a), the Company shall not pay Employee
any portion of his Base Compensation and Employee shall be on an unpaid leave of
absence.

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            (c) If the Employee's  disability  shall terminate at any time prior
to the expiration of the period described in subparagraph (b) of this Section 6,
then the Employee  shall return to full and active  employment  with the Company
under  the  terms of this  Agreement;  provided  that if he shall  again  become
disabled  within a period  of three  (3)  months  after  such  return,  and such
disability  is related to his original  disability,  then the Employee  shall be
deemed to have been continuously disabled from the date he incurred his original
disability.
            (d) Upon  expiration  of the  three (3) month  period  described  in
subparagraph  (b) of this  Section  6,  the  employment  of the  Employee  shall
terminate,  unless an additional leave of absence is granted by the Company,  in
which event the employment of the Employee  shall  terminate upon the expiration
of the additional leave of absence.
            (e) In the event the Employee shall incur a Partial  Disability then
during the period of the Partial  Disability,  the Employee's Base  Compensation
shall be equitably  adjusted  according to the time that he is able to devote to
the affairs of the Company.
            (f) In addition to the foregoing,  the Employee shall be entitled to
receive  the  amounts,  if  any,  as may be  payable  to  him by  reason  of his
disability under policies of insurance maintained by the Company.
            (g)   As used in this Agreement, the term "Total
Disability" shall mean a disability such that, for physical or

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mental reasons, the Employee is unable to perform any of his usual duties to the
Company on a  full-time  basis.  As used in this  Agreement,  the term  "Partial
Disability" shall mean a disability,  other than a total  disability,  such that
for  physical or mental  reasons,  the  Employee is unable to perform all of his
usual duties to the Company on a full-time basis.
      7.    Termination.
            (a) Termination by Death. If the Employee dies during the Employment
Period,  the Company's  obligations under this Agreement shall terminate six (6)
months  after the date of death and the  Employee's  estate shall be entitled to
all arrearages of Base  Compensation and expenses.  In addition,  the Employee's
estate (or such other named  beneficiary)  shall be entitled to the amounts,  if
any,  as may be  payable  to his  estate  or  beneficiaries  under  policies  of
insurance maintained by the Company.
            (b)  Termination  for  Cause.  This  Agreement  and  the  Employee's
employment  with  the  Company  may be  terminated  for  Cause  at any  time  in
accordance with  subparagraph (d) of this Section 7. In the event this Agreement
is terminated  for Cause,  the Employee  shall be entitled to all  arrearages of
Base  Compensation and expenses through the Date of Termination but shall not be
entitled  to  further  compensation.  As  used in this  Agreement,  and  without
limitation, the term "Cause" shall mean:
            (i) an act or acts of dishonesty constituting criminal
acts by the Employee resulting or intended to result directly or

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indirectly in gain to or personal enrichment of the Employee at the
Company's expense;
            (ii)  the commission of any crime involving fraud,
embezzlement or theft by the Employee against the Company;
            (iii) engaging in competition  with the Company,  including taking a
management  position with, or control of, a business engaged in the manufacture,
sale or distribution of a class of products or service which  constituted 15% or
more of the sales or gross  income of the Company and its  associated  companies
during the fiscal year of the Company  immediately  preceding the termination of
the Employee's employment.
            (c)  Termination  at the Option of the Employee.  This Agreement and
the Employee's employment with the Company may be terminated at any time, at the
election of the Employee, for Good Reason in accordance with subparagraph (d) of
this Section 7. In the event this Agreement is terminated  for Good Reason,  the
Employee shall be paid during the remainder of the Employment  Period  (computed
without  giving  effect  to  the  earlier  termination   hereunder),   his  Base
Compensation  (other than due to Partial Disability) at the rate in effect as of
the Date of Termination,  and shall continue to be entitled to employee benefits
as if he were still employed by the Company, until completion of such Employment
Period (computed without giving effect to the earlier termination hereunder). As
used in this  Agreement,  and without  limitation,  the term "Good Reason" shall
mean:

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            (i) the assignment to the Employee of duties  inconsistent  with the
office of Vice President and Chief Financial  Officer of the Company or his then
current  office,  the removal of the  Employee  from such office or  substantial
reduction   in  the   nature   or  status  of  the   Employee's   then   current
responsibilities;
            (ii) the reduction of the Employee's then current Base
Compensation (other than due to Partial Disability) ;
            (iii) the relocation of the Company's principal executive offices to
a location  more than fifty (50)  miles  from the  Company's  current  principal
executive  offices or the  transfer  of the  Employee  to a place other than the
Company's   principal  executive  offices  (excepting  required  travel  on  the
Company's  business in a manner  substantially  similar to the  Employee's  then
current business travel obligations); and
            (iv) the failure by the Company to continue to provide the  Employee
with  benefits at least as  favorable  as those in which the  Employee  was then
participating.
            (d)  Notice  of  Termination.   Any  purported  termination  of  the
Employee's  employment  shall be communicated by a written notice of termination
to the other party  hereto and specify the Date of  Termination  (the "Notice of
Termination").  Such notice shall  indicate a specific  terminated  provision in
this Agreement which is relied upon, recite the facts and circumstances  claimed
to provide the basis for such  termination  and specify the Date of Termination.
As used in this Agreement,  the term "Date of  Termination"  shall mean the date
specified in the Notice of Termination, which date

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shall not be less than  thirty  (30) nor more than sixty (60) days from the date
the Notice of Termination is given. If within thirty (30) days from the date the
Notice of Termination  is given,  the party  receiving such notice  notifies the
other  party that a dispute  exists  concerning  such  termination,  the Date of
Termination shall be the date on which the dispute is finally resolved. The Date
of  Termination  shall be extended by a notice of dispute only if such notice is
given in good faith and the party giving such notice  pursues the  resolution of
such dispute with reasonable diligence. Notwithstanding the pendency of any such
dispute,   the  Company  will  continue  to  pay  the  Employee  his  full  Base
Compensation  in effect as of the date of the Notice of Termination and continue
the Employee as a participant in all  compensation,  benefit and insurance plans
in which he was  participating  at such  date,  until  the  dispute  is  finally
resolved.  Amounts paid under this subparagraph (d) are in addition to all other
amounts due under this  Agreement and shall not be offset  against or reduce any
other amounts due under this Agreement.
      8. Change in Control. In the event of a Change in Control and, as a result
of such  Change in Control,  the  Employee is  terminated  without  Cause or the
Employee  elects to terminate his employment for any reason as a result thereof,
then the Employee shall receive the following benefits:
            (a) The Company shall pay to the Employee his full Base Compensation
at the rate in effect at the time of the Notice of Termination  through the Date
of Termination.

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            (b) In lieu of any further  Base  Compensation  payments for periods
subsequent to the Date of Termination,  the Company shall pay to the Employee as
severance pay not later than the fifth day following the Date of Termination,  a
lump sum payment (the  "Severance  Payment")  equal to 2.99 times the average of
the annual  Compensation  which was  payable to the  Employee by the Company and
includible in the  Employee's  gross income for federal  income tax purposes for
the five (5) calendar  years, or for the portion of such period during which the
Employee was actually  employed by the Company if the Employee has been employed
by the Company for less than five (5) calendar  years  preceding  the earlier of
the calendar year in which a Change in Control  occurred or the calendar year of
the Date of Termination (the "Base Period"). Such average shall be determined in
accordance with the provisions of Section  280G(d) of the Internal  Revenue Code
of  1986  as  amended  (the  "Code").  As  used  in  this  Agreement,  the  term
"Compensation"  shall  mean and  include  every  type  and form of  compensation
includible in the  Employee's  gross income in respect of his  employment by the
Company including  compensation income recognized as a result of the exercise of
stock options or sale of the stock so acquired,  except to the extent  otherwise
provided in  Congressional  or Joint  Committee  Reports or  temporary  or final
regulations interpreting Section 280G(d) of the Code.
            (c) The  Severance  Payment  shall be  reduced  by the amount of any
other  payment or the value of any  benefit  received  or to be  received by the
Employee in connection with the termination of his

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employment or contingent upon a Change in Control  (whether  payable pursuant to
the terms of this Agreement,  any other plan,  agreement or arrangement with the
Company)  unless (i) the Employee shall have  effectively  waived his receipt or
enjoyment  of such  payment  or  benefit  prior  to the date of  payment  of the
Severance  Payment,  (ii) in the opinion of tax counsel  selected by the Company
such other payment or benefit does not constitute a "parachute  payment"  within
the meaning of Section  280G(b)(2)  of the Code, or (iii) in the opinion of such
tax counsel,  the Severance Payment (in its full amount or as partially reduced,
as the case may be)  plus  all  other  payments  or  benefits  which  constitute
"parachute  payments"  within the meaning of Section  280G(b)(2) of the Code are
reasonable  compensation file services actually rendered,  within the meaning of
Section 280G(b)(4) of the Code, and such payments are deductible by the Company.
The  value  of any  non-cash  benefit  or any  deferred  cash  payment  shall be
determined  by  the  Company  in  accordance  with  the  principles  of  Section
280G(d)(3) and (4) of the Code.
            (d)  Except to the  extent  that  Congressional  or Joint  Committee
Reports or temporary or final regulations  interpreting Section 280G of the Code
specify that such  payments  would  result,  under  subsection  (c) above,  in a
reduction in the Severance Payment:
            (i) The Company shall pay to the Employee,  not later than the fifth
day following the Date of Termination, a lump sum amount equal to the sum of (x)
any bonus  compensation  which has been  allocated  or awarded for a fiscal year
preceding the Date of

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Termination  but has not yet been paid,  and (y) a pro rata portion of any bonus
compensation which the Employee has earned for the fiscal year in which the Date
of  Termination  occurs  determined by multiplying  the Employee's  prior years'
bonus  compensation by a fraction equal to the number of full calendar months in
the fiscal year prior to the Date of Termination over twelve.
            (ii) The Company shall also pay all legal fees and expenses incurred
by the  Employee as a result of such  termination  (including  all such fees and
expenses, if any, incurred in contesting or disputing any such termination or in
seeking to obtain or enforce any right or benefit provided by this Agreement).
            (e) If it is  established  pursuant  to a final  determination  of a
court or an Internal Revenue Service proceeding that,  notwithstanding  the good
faith of the  Employee  and the Company in applying the terms of this Section 8,
the aggregate  "parachute  payments"  paid are in an amount that would result in
any portion of such "parachute  payments" not being deductible by the Company by
reason of Section 280G of the Code,  then the Employee  shall have an obligation
to pay the Company  upon demand an amount equal to the sum of (i) the portion of
the aggregate  "parachute  payments" paid that would not be deductible by reason
of Section 280G of the Code and (ii)  interest on the amount set forth in clause
(i) of this  sentence  at the  applicable  Federal  rate (as  defined in Section
1274(d) of the Code) from the date of receipt of such  excess  until the date of
such payment.

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            (f) As used in the  Agreement,  the term  "Change in Control"  shall
mean a change in control of a nature  that would be  required  to be reported in
response  to Item  6(e) of  Schedule  14A of  Regulation  14A  issued  under the
Securities Exchange Act of 1934, as amended (the "Exchange Act") as in effect as
of the date  hereof  (regardless  of whether or not a Proxy  Statement  is being
filed pursuant to such Regulation at such time), or if Item 6(e) is no longer in
effect,  any subsequent  regulation  issued under the Exchange Act for a similar
purpose,  whether or not the Company is subject to such reporting  requirements;
provided,  that without limitation,  such a change in control shall be deemed to
have occurred if:
            (i)  any  "person"  other  than  the  Employee  is  or  becomes  the
"beneficial  owner" (as defined in Rule 13d-3 under the Exchange Act),  directly
or  indirectly,  of  securities of the Company  representing  25% or more of the
combined voting power of the Company's then outstanding securities;
            (ii) during any period of two  consecutive  years (not including any
period prior to the date of the Agreement),  individuals who at the beginning of
such period  constitute  the Board of  Directors,  and any new  director,  whose
election by the Board or nomination  for election by the Company's  stockholders
was approved by a vote of at least  two-thirds  of the  directors  then still in
office  who  either  were  directors  at the  beginning  of the  period or whose
election or nomination for elections was previously

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approved, cease for any reason to constitute a majority of the
Board; or
            (iii) the  business  of the  Company is  disposed  of by the Company
pursuant to a liquidation, sale of assets of the Company, or otherwise.
      9. Confidential  Information.  The Employee  acknowledges an obligation of
confidentiality  to the Company and shall not divulge,  disclose or  communicate
any trade  secret,  private or  confidential  information  or other  proprietary
knowledge of the Company or its associated companies obtained or acquired by him
while so employed.  This  restriction  shall apply after the  termination of the
Employee's employment without limit in point of time but shall cease to apply to
information  or  knowledge  which  may come  into  the  public  domain  or whose
disclosure  may be  required  by law or court  order or  pursuant to the written
consent of the Corporation.
      10. Return of Information.  Upon  termination of employment,  the Employee
agrees to not take with him and to deliver to the  Company all  records,  notes,
data, memoranda,  models,  equipment,  blueprints,  drawings,  manuals, letters,
reports and all other materials of a secret or  confidential  nature relating to
the business of the Company which are in possession or control of the Employee.
      11.   General Provisions.
            (a)   This Agreement contains the entire transaction
between the parties, and there are no other representations,

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warranties, conditions or agreements relating to the subject matter
of this Agreement.
            (b)  The  waiver  by any  party  of any  breach  or  default  of any
provision of this Agreement shall not operate or be construed as a waiver of any
subsequent breach.
            (c)  This  Agreement  may  not be  changed  orally  but  only  by an
Agreement  in  writing  duly  executed  on  behalf of the  party  against  which
enforcement of any waiver, change, modification, consent or discharge is sought.
            (d) This Agreement shall be binding upon and be enforceable  against
the  Company  and  its  successors  and  assigns.  Insofar  as the  Employee  is
concerned, this Agreement is personal and cannot be assigned.
            (e) This Agreement may be executed in one or more counterparts, each
of which shall be deemed an original, but all of which together shall constitute
one and the same instrument.
            (f) This Agreement shall be construed  pursuant to and in accordance
with the laws of the State of New Jersey.
            (g) If any term or provision of this  Agreement is held or deemed to
be  invalid  or  unenforceable,  in whole or in  part,  by a court of  competent
jurisdiction,  this  Agreement  shall  be  ineffective  to the  extent  of  such
invalidity or  unenforceability  without  rendering invalid or unenforceable the
remaining terms and provisions of this Agreement.
            (h)   Any dispute, grievance or controversy arising under
or in connection with this Agreement shall be referred to the Board

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of Directors of the Company and shall be dealt with by personal discussion,  and
if not  satisfactorily  resolved,  shall be submitted to  arbitration  under the
Rules of the American Arbitration Association in New York City.
            (i) Any consent of the Company  required under this Agreement  shall
not be unreasonably withheld or delayed.
      IN WITNESS  WHEREOF,  the parties have executed this Agreement on the date
first above written.
                                    COMPANY:

                                    Bio-Reference Laboratories, Inc.



                                    By /s/Marc D. Grodman
                                      President
                                      Duly Authorized


                                    EMPLOYEE:



                                    /s/Sam Singer
                                    Sam Singer





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