1. Name and Address of Reporting Person
   Jepsen, John R.
   199 Benson Road
   Middlebury, CT 06749
   USA
2. Issuer Name and Ticker or Trading Symbol
   Crompton Corporation
3. IRS or Social Security Number of Reporting Person (Voluntary)
4. Statement for Month/Day/Year
   01/21/2003
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)
   Vice President & Treasurer
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- |2A.Execu- |3. Trans-|4. Securities Acquired (A)|5. Amount of  |6. Owner-  |7. Nature   |
|                              |   action |   action |   action|   or Disposed of (D)     |Securities    |   ship    |   of In-   |
|                              |   Date   |   Date   |   Code  |                          |Beneficially  |   Form:   |   direct   |
|                              |          |          |         |                          |Owned         |   Direct  |   Bene-    |
|                              |  (Month/ |  (Month/ |         |                          |Following     |   (D) or  |   ficial   |
|                              |   Day/   |   Day/   +-----+---+-----------+---+----------+Reported      |   Indirect|   Owner-   |
|                              |   Year)  |   Year)  |Code |V  |Amount     |A/D|Price     |Transaction(s)|   (I)     |   ship     |
+------------------------------+----------+----------+-----+---+-----------+---+----------+--------------+-----------+------------+
                                                                                        
Common Stock                                                                               8353           D
Common Stock                                                                               1296.587       I           ESOP TRUST





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

+----------+--------+-------+-------+---------+-----------+---------------------+----------------+----------+-------+-------+------+
|1.        |2.      |3.     |3A.    |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- |Trans- |Execu- |         |Number of  |                     |Securities      |          |ities  |Secur- |of    |
|          |sion or |action |tion   |         |Derivative |Date Exercisable     +-------+--------+          |Benefi-|ity:   |In-   |
|          |Exercise|Date   |Date   |         |Securities |and Expiration Date  |       |Amount  |          |cially |Direct |direct|
|          |Price of|       |       |Transac- |Acquired(A)|(Month/Day/Year)     |       |or      |          |Owned  |(D) or |Bene- |
|Title of  |Deriv-  |(Month/|(Month/|tion Code|Disposed(D)+----------+----------+       |Number  |Price of  |       |In-    |ficial|
|Derivative|ative   | Day/  | Day/  +------+--+-----+-----+Date Exer-|Expira-   |       |of      |Derivative|       |direct |Owner-|
|Security  |Security|Year)  |Year)  |Code  |V |(A)  |(D)  |cisable   |tion Date |Title  |Shares  |Security  |       |(I)    |ship  |
+----------+--------+-------+-------+------+--+-----+-----+----------+----------+-------+--------+----------+-------+-------+------+
                                                                                
NQ Stock    $6.38    01/21/2         A     8           01/21/2004 02/20/2013 Common  8        $0.0000    8       D
Option               003                                                         Stock
(Right to
Buy)
NQ Stock    $7.25                                                     11/21/2012 Common                      2132    D
Option                                                                           Stock
(Right to
Buy)
NQ Stock    $7.92                                                     11/22/2011 Common                      10000   D
Option                                                                           Stock
(Right to
Buy)
NQ Stock    $8.1562                                                   11/30/2010 Common                      20000   D
Option                                                                           Stock
(Right to
Buy)
NQ Stock    $8.343                                                    11/19/2009 Common                      22642   D
Option                                                                           Stock
(Right to
Buy)
ISO Stock   $6.38    01/21/2         A     29992       01/21/2004 01/21/2013 Common  29992    $0.0000    29992   D
Option               003                                                         Stock
(Right to
Buy)
ISO Stock   $7.25                                                     10/22/2012 Common                      7868    D
Option                                                                           Stock
(Right to
Buy)
ISO Stock   $7.92                                                     10/23/2011 Common                      10000   D
Option                                                                           Stock
(Right to
Buy)
ISO Stock   $8.343                                                    10/19/2009 Common                      27358   D
Option                                                                           Stock
(Right to
Buy)
ISO Stock   $14.3438                                                  10/14/2008 Common                      5000    D
Option                                                                           Stock
(Right to
Buy)

Explanation of Responses:


Options will vest as follows:  8 on 1/21/2004.

Options will vest as follows:  9,992 on 1/21/2004, 10,000 on 1/21/2005 and
10,000 on 1/21/2006.



SIGNATURE OF REPORTING PERSON
/s/ John R. Jepsen

DATE
01/23/2003