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                                                                    EXHIBIT 21.1


                     SCHEDULE OF SUBSIDIARIES OF REGISTRANT







1.     Dynamex Operations East, a Delaware corporation

                10,000 authorized shares of common stock, $0.01 par
                value, 1,000 of which are issued and outstanding and
                registered in the name of Dynamex Inc.

2.     Dynamex Operations West, a Delaware corporation

                10,000 authorized shares of common stock, $0.01 par
                value, 1,000 of which are issued and outstanding and
                registered in the name of Dynamex Inc.

3.     Dynamex Canada Inc., a Canadian federal corporation (formerly Parcelway
       Courier Systems Canada Ltd., an Alberta corporation)

                Unlimited number of authorized common shares, one of
                which is issued and outstanding in the name of
                Dynamex Inc.; Unlimited number of authorized
                preference shares, 3,750,000 of which are issued and
                outstanding in the name of Dynamex Inc.

4.     Parcelway Courier Systems (B.C.) Ltd., a British Columbia corporation

                20,000 authorized common shares, no par value, 65 of
                which are issued and outstanding in the name of
                Parcelway Courier Systems Canada Ltd.

5.     Alpine Enterprises Ltd., a Manitoba corporation

                Unlimited number of authorized Class A Voting Common Shares, 290
                of which are issued and outstanding in the name of Dynamex
                Canada Inc., unlimited Class B Voting Shares, unlimited Class C
                Voting Common Shares, unlimited Class D Voting Common Shares,
                unlimited Class A Non-Voting Common Shares, unlimited Class B
                Non-Voting Common Shares, unlimited Class C Common Non-Voting
                Shares, unlimited Class D Common Non-Voting Shares, and an
                unlimited number of Preference Shares

6.     Road Runner Transportation, Inc.

                25,000 authorized common shares (consisting of 7,000
                voting, 5,000 non-voting and 13,000 undesignated), no
                par value; of which 4,363.9998 non-voting are issued
                and outstanding in the name of Dynamex Inc., and of
                which 6,545 voting are issued and outstanding in the
                name of Dynamex Inc.
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 7.     New York Document Exchange Corp.
 
                 200 shares of common stock are authorized, no par
                 value, of which 150 shares are issued and outstanding
                 in the name of Dynamex Inc.

 8.     U.S.C. Management Systems, Inc.
 
                 200 shares of common stock are authorized, no par
                 value, of which 91.33 shares are issued and
                 outstanding in the name of Dynamex Inc.

 9.     Cannonball, Inc.

                 71,450  shares of common stock are authorized,
                 $1.00 per value, of which 69,350 shares are issued
                 and outstanding in the name of Dynamex Inc.

10.     Dynamex Dedicated Fleet Services, Inc.

                 10,000 shares of common stock are authorized, $.01
                 par value, of which 1,000 shares are issued and 
                 outstanding in the name of Dynamex Inc.