1. Name and Address of Reporting Person
   ACKERMAN, THOMAS F.
   251 Ballardvale Street
   Wilmington, MA 01887
   USA
2. Issuer Name and Ticker or Trading Symbol
   Charles River Laboratories Int'l., Inc (CRL)
3. IRS or Social Security Number of Reporting Person (Voluntary)
4. Statement for Month/Year
   5/2002
5. If Amendment, Date of Original (Month/Day/Year)
6. Relationship of Reporting Person(s) to Issuer (Check all applicable)
   ( ) Director                   ( ) 10% Owner
   (X) Officer (give title below) ( ) Other (specify below)
   Sr. Vp and CFO
7. Individual or Joint/Group Filing (Check Applicable Line)
   (X) Form filed by One Reporting Person
   ( ) Form filed by More than One Reporting Person

TABLE I -- Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

+---------------------------------+----------+-------------+-----------------------------+----------------+-----------+------------+
|1. Title of Security             |2. Trans- |3. Trans-    |4. Securities Acquired (A)   |5. Amount of    |6. Owner-  |7. Nature   |
|                                 |   action |   action    |   or Disposed of (D)        |   Securities   |   ship    |   of In-   |
|                                 |   Date   |   Code      |                             |   Beneficially |   Form:   |   direct   |
|                                 |          |             |                             |   Owned at     |   Direct  |   Bene-    |
|                                 |  (Month/ |             |                             |   End of       |   (D) or  |   ficial   |
|                                 |   Day/   +-------+-----+-----------+------+----------+   Month        |   Indirect|   Owner-   |
|                                 |   Year)  |Code   |V    |Amount     |A/D   |Price     |                |   (I)     |   ship     |
+---------------------------------+----------+-------+-----+-----------+------+----------+----------------+-----------+------------+
                                                                                            
Common Stock                       05/02/2002 S         -6000       D      $33.1500   19767            D





TABLE II -- Derivative Securities Acquired, Disposed of, or Beneficially Owned

+-------------+--------+----------+---------+-----------+---------------------+----------------+----------+--------+-------+-------+
|1.           |2.      |3.        |4.       |5.         |6.                   |7.              |8.        |9.      |10.    |11.    |
|             |        |          |         |           |                     |                |          |Number  |Owner- |       |
|             |        |          |         |           |                     |                |          |of      |ship   |       |
|             |        |          |         |           |                     |                |          |Deriv-  |Form of|       |
|             |        |          |         |           |                     |Title and Amount|          |ative   |Deriv- |       |
|             |        |          |         |           |                     |of Underlying   |          |Secur-  |ative  |Nature |
|             |Conver- |          |         |Number of  |                     |Securities      |          |ities   |Secur- |of     |
|             |sion or |          |         |Derivative |Date Exercisable     +-------+--------+          |Benefi- |ity:   |In-    |
|             |Exercise|          |         |Securities |and Expiration Date  |       |Amount  |          |cially  |Direct |direct |
|             |Price of|Transac-  |Transac- |Acquired(A)|(Month/Day/Year)     |       |or      |          |Owned   |(D) or |Bene-  |
|Title of     |Deriv-  |tion Date |tion Code|Disposed(D)+----------+----------+       |Number  |Price of  |at End  |In-    |ficial |
|Derivative   |ative   |(Month/   +------+--+-----+-----+Date Exer-|Expira-   |       |of      |Derivative|of      |direct |Owner- |
|Security     |Security|Day/Year) |Code  |V |(A)  |(D)  |cisable   |tion Date |Title  |Shares  |Security  |Month   |(I)    |ship   |
+-------------+--------+----------+------+--+-----+-----+----------+----------+-------+--------+----------+--------+-------+-------+
                                                                                  

Explanation of Responses:


This trade occured pursuant to a rule 10b5-1 trading plan established December
2001.



SIGNATURE OF REPORTING PERSON
/s/ THOMAS F. ACKERMAN

DATE
06/04/2002