SC 13D

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934
(Amendment No.  )*

Dynamex Inc.

(Name of Issuer)

Common Stock, $0.01 par value

(Title of Class of Securities)

26784F103

(CUSIP Number)

Jacob D. Smith
General Counsel
Luther King Capital Management Corporation
301 Commerce Street, Suite 1600
Fort Worth, Texas 76102
(817) 332-3235

(Name, Address and Telephone Number of Person Authorized to
Receive Notices and Communications)

October 4, 2010

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. þ

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See Rule 13d-7 for other parties to whom copies are to be sent.

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. 26784F103 

1	NAMES OF REPORTING PERSONS LKCM Private Discipline Master Fund, SPC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Cayman Islands
		7	SOLE VOTING POWER
NUMBER OF			290,000
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			290,000
WITH		10	SHARED DISPOSITIVE POWER
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	290,000
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	3.0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	OO

Page 2 of 12

CUSIP No. 26784F103 

1	NAMES OF REPORTING PERSONS LKCM Investment Partnership, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Texas
		7	SOLE VOTING POWER
NUMBER OF			197,741
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			197,741
WITH		10	SHARED DISPOSITIVE POWER
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	197,741
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	2.0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	PN

Page 3 of 12

CUSIP No. 26784F103 

1	NAMES OF REPORTING PERSONS LKCM Investment Partnership II, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Texas
		7	SOLE VOTING POWER
NUMBER OF			7,791
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			7,791
WITH		10	SHARED DISPOSITIVE POWER
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	7,791
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	0.1%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	PN

Page 4 of 12

CUSIP No. 26784F103 

1	NAMES OF REPORTING PERSONS LKCM Capital Group, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Texas
		7	SOLE VOTING POWER
NUMBER OF			290,000
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			290,000
WITH		10	SHARED DISPOSITIVE POWER
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	290,000
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	3.0%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	OO

Page 5 of 12

CUSIP No. 26784F103 

1	NAMES OF REPORTING PERSONS LKCM Investment Partnership GP, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Texas
		7	SOLE VOTING POWER
NUMBER OF			205,532
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			205,532
WITH		10	SHARED DISPOSITIVE POWER
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	205,532
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	2.1%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	OO

Page 6 of 12

CUSIP No. 26784F103 

1	NAMES OF REPORTING PERSONS Luther King Capital Management Corporation
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	Delaware
		7	SOLE VOTING POWER
NUMBER OF			550,482
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			550,482
WITH		10	SHARED DISPOSITIVE POWER
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	550,482
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	5.6%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IA, CO

Page 7 of 12

CUSIP No. 26784F103 

1	NAMES OF REPORTING PERSONS J. Luther King, Jr.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	United States
		7	SOLE VOTING POWER
NUMBER OF			550,482
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			550,482
WITH		10	SHARED DISPOSITIVE POWER
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	550,482
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	5.6%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IN

Page 8 of 12

CUSIP No. 26784F103 

1	NAMES OF REPORTING PERSONS J. Bryan King
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS)
	(a)   o
	(b)   þ
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	N/A
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e)
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	United States
		7	SOLE VOTING POWER
NUMBER OF			550,482
SHARES		8	SHARED VOTING POWER
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER
REPORTING
PERSON			550,482
WITH		10	SHARED DISPOSITIVE POWER
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	550,482
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	5.6%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	IN

Page 9 of 12

Item 1. Security and Issuer

This Schedule 13D relates to the Common Stock, $0.01 par value (“Common Stock”), of Dynamex Inc., a Delaware corporation (the “Issuer”). The address of the principal executive offices of the Issuer is 5429 LBJ Freeway, Suite 1000, Dallas, Texas 75240.

Item 2. Identity and Background

(a) The names of the persons filing this Schedule 13D are LKCM Private Discipline Master Fund, SPC, a Cayman Islands segregated portfolio company (“PDP”), LKCM Investment Partnership, L.P., a Texas limited partnership (“LIP”), LKCM Investment Partnership II, L.P., a Texas limited partnership (“LIP II”), LKCM Capital Group, LLC, a Texas limited liability company (“LKCM Capital Group”), LKCM Investment Partnership GP, LLC, a Texas limited liability company (“LIP GP”), Luther King Capital Management Corporation, a Delaware corporation (“LKCM”), J. Luther King, Jr. and J. Bryan King (collectively, the “Reporting Persons”).

(b) The principal business address of PDP is c/o Spectrum Global Fund Administration, Piccadilly Centre, 3rd Floor, PO Box 10243, Grand Cayman KY1-1003, Cayman Islands, and the principal business address of the other Reporting Persons is 301 Commerce Street, Suite 1600, Fort Worth, Texas 76102.

(c) PDP, LIP, LIP II, and other clients for which LKCM exercises discretionary investment authority are the beneficial holders of the shares of Common Stock reported herein. LKCM Capital Group is the sole member of LKCM Alternative Management, LLC, a Delaware limited liability company and the general partner of LKCM Private Discipline Management, L.P., a Delaware limited partnership and the sole holder of the management shares of PDP. LIP GP is the general partner of each of LIP and LIP II. LKCM is the investment manager of PDP, LIP and LIP II. J. Luther King, Jr. and J. Bryan King are controlling members and shareholders, as applicable, of LKCM Capital Group, LIP GP, and LKCM. The principal business of each of PDP, LIP and LIP II is purchasing, holding, and selling securities for investment purposes, and the principal business of the other Reporting Persons is investment management.

(d) and (e) During the past five years, none of the Reporting Persons has been convicted in a criminal proceeding or been a party to a civil proceeding, in either case of the type specified in Items 2(d) or (e) of Schedule 13D.

(f) PDP is organized under the laws of the Cayman Islands. LKCM Capital Group, LIP, LIP II, and LIP GP are organized under the laws of Texas. LKCM is organized under the laws of Delaware. J. Luther King, Jr. and J. Bryan King are citizens of the United States.

Item 3. Source and Amount of Funds or Other Consideration

PDP has acquired 290,000 shares of Common Stock in open market transactions for an aggregate purchase price of approximately $5,680,000 using working capital. LIP has acquired 197,741 shares of Common Stock in open market transactions for an aggregate purchase price of approximately $3,960,000 using working capital. LIP II has acquired 7,791 shares of Common Stock in open market transactions for an aggregate purchase price of approximately $95,000 using working capital. LKCM has acquired 54,950 shares of Common Stock on behalf of other clients for which LKCM exercises discretionary investment authority in open market transactions for an aggregate purchase price of approximately $794,000 using working capital.

Item 4. Purpose of Transaction

The Reporting Persons have acquired the shares of Common Stock for investment purposes. The Reporting Persons from time to time intend to review their investment in the Issuer on the basis of various factors, including the Issuer’s business, financial condition, results of operations and prospects, general economic and industry conditions, the securities markets in general and those for the Issuer’s securities in general, as well as other developments and other investment opportunities. Based upon such review, the Reporting Persons intend to take such actions in the future as they deem appropriate in light of the circumstances existing from time to time, which may include further acquisitions of Common Stock or disposal of all of the shares of Common Stock currently owned by the Reporting Persons or otherwise acquired by the Reporting Persons, either in the open market or privately negotiated transactions, with or without prior notice.

Page 10 of 12 

In addition, the Reporting Persons may engage in communications with one or more shareholders, officers or directors of the Issuer, including discussions regarding the Issuer’s operations and strategic direction and ideas that, if effected, could result in, among other things, any of the matters identified in Item 4(a)-(j) of Schedule 13D. The Reporting Persons reserve their right, based on all relevant factors and subject to applicable law, at any time and from time to time, to review or reconsider their position, change their purpose, take other actions (including actions that could involve one or more of the types of transactions or have one or more the results described in Item 4(a)-(j) of Schedule 13D) or formulate and implement plans or proposals with respect to any of the foregoing.

Item 5. Interest in Securities of the Issuer

(a) As of October 4, 2010, the Reporting Persons may be deemed to beneficially own 550,482 shares of Common Stock (which represents approximately 5.6% of the outstanding Common Stock based upon information contained in the Issuer’s Annual Report on Form 10-K for its fiscal year ended July 31, 2010).

(b)

	Sole		Shared		Sole		Shared
	Voting		Voting		Dispositive		Dispositive
	Power		Power		Power		Power
LKCM Private Discipline Master Fund, SPC		290,000		0		290,000		0
LKCM Investment Partnership, L.P.		197,741		0		197,741		0
LKCM Investment Partnership II, L.P.		7,791		0		7,791		0
LKCM Capital Group, LLC		290,000		0		290,000		0
LKCM Investment Partnership GP, LLC		205,532		0		205,532		0
Luther King Capital Management Corporation		550,482		0		550,482		0
J. Luther King, Jr.		550,482		0		550,482		0
J. Bryan King		550,482		0		550,482		0

(c) During the past sixty days, the Reporting Persons have sold the following shares of Common Stock in open market transactions.

Date	Shares		Price
9/21/2010		14,468	$	14.6083
10/4/2010		4,000	$	21.0281

(d) Not applicable.

(e) Not applicable.

Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to Securities of the Issuer

Except as otherwise provided herein, there are no contracts, arrangements, understandings, or relationships between the Reporting Persons and any other person with respect to the securities of the Issuer.

Item 7. Material to Be Filed as Exhibits

Exhibit 1      Joint Filing Agreement, dated October 4, 2010, by and among the Reporting Persons.

Page 11 of 12 

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: October 4, 2010

LKCM Private Discipline Master Fund, SPC
By:	LKCM Private Discipline Management, L.P., sole holder of its management shares
By:	LKCM Alternative Management, LLC, its general partner
By:   LKCM Capital Group, LLC, its sole member
By:	/s/ J. Bryan King
	J. Bryan King, President
LKCM Investment Partnership, L.P.
By:	LKCM Investment Partnership GP, LLC, its general partner
By:	/s/ J. Luther King, Jr.
	J. Luther King, Jr., President
LKCM Investment Partnership II, L.P.
By:	LKCM Investment Partnership GP, LLC, its general partner
By:	/s/ J. Luther King, Jr.
	J. Luther King, Jr., President
LKCM Capital Group, LLC
By:	/s/ J. Bryan King
	J. Bryan King, President
LKCM Investment Partnership GP, LLC
By:	/s/ J. Luther King, Jr.
	J. Luther King, Jr., President
Luther King Capital Management Corporation
By:	/s/ J. Bryan King
	J. Bryan King, Vice President
/s/ J. Bryan King
J. Bryan King
/s/ J. Luther King, Jr.
J. Luther King, Jr.

Page 12 of 12 

EX-99.1

EXHIBIT 1 — JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k) promulgated under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them a Statement on Schedule 13D (including amendments thereto) with regard to the Common stock, $0.01 par value, of Dynamex Inc. and further agree that this Joint Filing Agreement be included as an Exhibit to such joint filings. In evidence thereof, the undersigned, being duly authorized, hereby execute this Agreement as of October 4, 2010.

LKCM Private Discipline Master Fund, SPC
By:	LKCM Private Discipline Management, L.P., sole holder of its management shares
By:	LKCM Alternative Management, LLC, its general partner
By:   LKCM Capital Group, LLC, its sole member
By:	/s/ J. Bryan King
	J. Bryan King, President
LKCM Investment Partnership, L.P.
By:	LKCM Investment Partnership GP, LLC, its general partner
By:	/s/ J. Luther King, Jr.
	J. Luther King, Jr., President
LKCM Investment Partnership II, L.P.
By:	LKCM Investment Partnership GP, LLC, its general partner
By:	/s/ J. Luther King, Jr.
	J. Luther King, Jr., President
LKCM Capital Group, LLC
By:	/s/ J. Bryan King
	J. Bryan King, President
LKCM Investment Partnership GP, LLC
By:	/s/ J. Luther King, Jr.
	J. Luther King, Jr., President
Luther King Capital Management Corporation
By:	/s/ J. Bryan King
	J. Bryan King, Vice President
/s/ J. Bryan King
J. Bryan King
/s/ J. Luther King, Jr.
J. Luther King, Jr.