Set forth below is a summary of the material  terms of the  informal  consulting
arrangement between Kronos Worldwide, Inc. ("Kronos") and Dr. Larry A. Wigdor

Dr.  Wigdor  will  provide  ongoing  management   involvement  in  Kronos'  TiO2
operations.

The  consultancy  will begin on August 1, 2003 and may be  terminated  by either
party at any time.

Beginning  on August 1,  2003 Dr.  Wigdor  will  receive  a monthly  payment  of
$84,000.

Dr. Widgor received a payment of $461,000 on August 1, 2003.

Dr. Widgor received a payment of $461,000 on February 1, 2004 following  Kronos'
achievement  of 2003 segment profit of $130 million (as Kronos defines that term
internally).

Beginning in 2004, Dr. Wigdor will receive annual payments that are no less than
the  average  bonus  paid to the  three  executives  of NL and  Kronos  combined
receiving  the highest paid bonuses for 2004 and 2005,  respectively,  excluding
the Chief Executive Officer of NL.

If Kronos  terminates the consultancy  arrangement  prior to September 30, 2005,
Dr. Wigdor will receive eight months  compensation,  medical and dental coverage
through  September 30, 2005. In addition,  if the  arrangement  is terminated in
2004 or  thereafter,  Dr.  Wigdor will receive a pro-rata  portion of the annual
payment for the year in which the termination occurs.

The arrangement  provides Dr. Wigdor various other benefits,  such as an office,
secretarial  support,  certain  indemnities  and health care and related welfare
benefits.