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Exhibit 31.1


CERTIFICATION


PURSUANT TO 17 CFR
240.13a-14


PROMULGATED UNDER


SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002






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|1. | I have reviewed this quarterly report on
    Form 10-Q of
    Celanese Holdings LLC;                                                                                                                                                                                                                                                              
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|2. | Based on my knowledge, this quarterly report does not contain
    any untrue statement of a material fact or omit to state a
    material fact necessary to make the statements made, in light of
    the circumstances under which such statements were made, not
    misleading with respect to the period covered by this quarterly
    report;
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|3. | Based on my knowledge, the financial statements, and other
    financial information included in this quarterly report, fairly
    present in all material respects the financial condition,
    results of operations and cash flows of the registrant as of,
    and for, the periods presented in this quarterly report;                       
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|4. | The registrants other certifying officer and I are
    responsible for establishing and maintaining disclosure controls
    and procedures (as defined in Exchange Act
    Rules 13a-15(e)
    and 15d-15(e)) for the
    registrant and we have:                                                                                                



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| | (a) | designed such disclosure controls and procedures, or caused such
    disclosure controls and procedures to be designed under our
    supervision, to ensure that material information relating to the
    registrant, including its consolidated subsidiaries, is made
    known to us by others within those entities, particularly during
    the period in which this quarterly report is being prepared;



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| | (b) | [Reserved]



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| | (c) | evaluated the effectiveness of the registrants disclosure
    controls and procedures and presented in this quarterly report
    our conclusions about the effectiveness of the disclosure
    controls and procedures, as of the end of the period covered by
    this report based on such evaluation; and



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| | (d) | disclosed in this report any change in the registrants
    internal control over financial reporting (as defined in
    Exchange Act
    Rules 13a-15(f)
    and 15d-15(f)) that
    occurred during the registrants most recent fiscal quarter
    (the registrants fourth fiscal quarter in the case of an
    annual report) that has materially affected, or is reasonably
    likely to materially affect, the registrants internal
    control over financial reporting; and



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|5. | The registrants other certifying officer and I have
    disclosed, based on our most recent evaluation of internal
    control over financial reporting, to the registrants
    auditors and the audit committee of registrants Board of
    Directors (or persons performing the equivalent functions):



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| | (a) | all significant deficiencies and material weaknesses in the
    design or operation of internal control over financial reporting
    which are reasonably likely to adversely affect the
    registrants ability to record, process, summarize and
    report financial information; and



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| | (b) | any fraud, whether or not material, that involves management or
    other employees who have a significant role in the
    registrants internal control over financial reporting.





| |                                      
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| | /s/ David N. Weidman                 
| |                                      
| | David N. Weidman                     
| | President and Chief Executive Officer