SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* SIMMONS HAROLD C (Last) (First) (Middle) THREE LINCOLN CENTRE 5430 LBJ FREEWAY STE 1700 (Street) DALLAS TX 75240-2697 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol KRONOS WORLDWIDE INC [ KRO ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director X 10% Owner X Officer (give title below) Other (specify below) Chairman of the Board & CEO
	3. Date of Earliest Transaction (Month/Day/Year) 05/15/2008
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. 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 (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock $0.01 par value	05/15/2008		A(1)		500	A	(1)	152,867	D
Common Stock $0.01 par value								28,995,021	I	by Valhi(2)
Common Stock $0.01 par value								17,516,132	I	by NL(3)
Common Stock $0.01 par value								5,203	I	by TFMC(4)
Common Stock $0.01 par value								36,356	I	by Spouse(5)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Shares issued for no cash consideration to nonemployee directors under the Kronos Worldwide, Inc. 2003 Long-Term Incentive Plan.

2. Directly held by Valhi, Inc. See the Additional Information filed as Exhibit 99 to this statement for a description of the relationship to the reporting person.

3. Directly held by NL Industries, Inc. See the Additional Information filed as Exhibit 99 to this statement for a description of the relationship to the reporting person.

4. Directly held by TIMET Finance Management Company. See the Additional Information filed as Exhibit 99 to this statement for a description of the relationship to the reporting person.

5. Directly held by the reporting person's spouse. The reporting person disclaims beneficial ownership of these shares

Remarks:

Exhibit Index Exhibit 99 - Additional Information

	A. Andrew R. Louis, Attorney-in-fact, for Harold C. Simmons	05/16/2008
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

Exhibit 99 Additional Information

     Valhi,  Inc.  ("Valhi"),  NL  Industries,  Inc.  ("NL")  and TIMET  Finance
Management  Company ("TFMC") are the holders of 59.2%, 35.8% and less than 0.1%,
respectively,  of the  outstanding  shares of common stock,  par value $0.01 per
share ("Common Stock"), of the issuer.

     Titanium Metals Corporation ("TIMET") directly owns 100% of the outstanding
common stock of TFMC. Valhi Holding Company ("VHC"),  Harold C. Simmons' spouse,
The Combined Master Retirement Trust (the "CMRT"),  Harold C. Simmons, NL, Valhi
and  the  Harold  Simmons  Foundation  (the  "Foundation")  are the  holders  of
approximately  26.9%, 11.7%, 8.5%, 4.0%, 0.8%, 0.5% and 0.2%,  respectively,  of
the outstanding common stock of TIMET. NL's percentage ownership of TIMET common
stock includes 0.3% directly held by a subsidiary of NL.

     Valhi and TFMC are the  direct  holders  of  approximately  83.1% and 0.5%,
respectively,  of the outstanding  common stock of NL. VHC, the Foundation,  the
TFMC  and  CMRT  are  the  direct  holders  of  92.6%,   0.9%,  0.7%  and  0.1%,
respectively,  of the outstanding common stock of Valhi. Dixie Rice Agricultural
Corporation,  Inc.  ("Dixie Rice") is the direct holder of 100% the  outstanding
common stock of VHC.  Contran  Corporation  ("Contran") is the holder of 100% of
the outstanding common stock of Dixie Rice.

     Substantially all of Contran's  outstanding  voting stock is held by trusts
established for the benefit of certain  children and  grandchildren of Harold C.
Simmons (the "Trusts"),  of which Mr. Simmons is the sole trustee, or is held by
Mr. Simmons or persons or entities  related to Mr.  Simmons.  As sole trustee of
the Trusts,  Mr. Simmons has the power to vote and direct the disposition of the
shares of Contran stock held by the Trusts.  Mr.  Simmons  disclaims  beneficial
ownership of all Contran shares that the Trusts hold.

     Harold C. Simmons is the chairman of the board and chief executive  officer
of each of the  issuer  and NL and the  chairman  of the board of each of Valhi,
TIMET, VHC, Dixie Rice and Contran.

     The Foundation  directly holds approximately 0.2% of the outstanding shares
of TIMET common stock and 0.9% of the outstanding  shares of Valhi common stock.
The Foundation is a tax-exempt  foundation  organized for  charitable  purposes.
Harold C. Simmons is the chairman of the board of the Foundation.

     The CMRT directly holds  approximately  8.5% of the  outstanding  shares of
TIMET common  stock and 0.1% of the  outstanding  shares of Valhi common  stock.
Contran  sponsors the CMRT,  which permits the  collective  investment by master
trusts that  maintain the assets of certain  employee  benefit plans Contran and
related companies adopt. Harold C. Simmons is the sole trustee of the CMRT and a
member of the  trust  investment  committee  for the  CMRT.  Contran's  board of
directors selects the trustee and members of the trust investment  committee for
the CMRT. Mr.  Simmons is a participant  in one or more of the employee  benefit
plans that invest through the CMRT.

     By virtue of the  holding  of the  offices,  the  stock  ownership  and his
services as trustee, all as described above, (a) Harold C. Simmons may be deemed
to control such entities and (b) Mr. Simmons and certain of such entities may be
deemed to possess  indirect  beneficial  ownership  of shares  directly  held by
certain of such other entities.  However,  Mr. Simmons disclaims such beneficial
ownership of the shares beneficially owned directly or indirectly by any of such
entities,  except to the extent of his vested  beneficial  interest,  if any, in
shares held by the CMRT. Mr. Harold Simmons  disclaims  beneficial  ownership of
all shares of Common Stock that Valhi, NL or TFMC directly holds.

     Harold C.  Simmons'  spouse is the direct owner of 36,356  shares of Common
Stock,  269,775  shares of NL common  stock,  21,167,875  shares of TIMET common
stock and 43,400  shares of Valhi  common  stock.  Mr.  Simmons may be deemed to
share indirect  beneficial  ownership of such shares.  Mr. Simmons disclaims all
such beneficial ownership.

     Harold C. Simmons  directly holds 152,867  shares of Common Stock,  879,600
shares of NL common  stock,  7,174,239  shares of TIMET  common  stock and 3,383
shares of Valhi common stock.

     A trust,  of which  Harold C.  Simmons and his spouse are  trustees and the
beneficiaries  are the  grandchildren  of his  spouse,  is the direct  holder of
17,423 of TIMET  common  stock and  36,500  shares of Valhi  common  stock.  Mr.
Simmons,  as  co-trustee  of this  trust,  has the power to vote and  direct the
disposition  of the shares of Valhi common stock the trust  holds.  Mr.  Simmons
disclaims beneficial ownership of any shares that this trust holds.

     NL and a subsidiary of NL directly own  3,522,967  and 1,186,200  shares of
Valhi common stock,  respectively.  Pursuant to Delaware  law,  Valhi treats the
shares of Valhi  common stock that NL and the  subsidiary  of NL own as treasury
stock for voting  purposes.  For the  purposes  of the  percentage  calculations
herein, such shares are not deemed outstanding.