1


                                                                    EXHIBIT 23.1

                    CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS

     As independent public accountants, we hereby consent to the incorporation
of our reports included in this Form 10-K, into the Company's previously filed
Registration Statement File Nos. 0-17136, 33-33281, 33-40564/33-40563, 33-63411,
333-5869, 333-48683, 333-67269, 333-75547/333-75549, 33-42272, 33-63409,
33-64123, 333-47301, 333-36474, 333-36476, 33-64213, 333-36474, 333-36476,
333-44546 and 333-54022.

ARTHUR ANDERSEN LLP

Houston, Texas
June 8, 2001