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Exhibit 31.1
  CERTIFICATIONPURSUANT TO 17 CFR
    240.13a-14
    PROMULGATED UNDER
    SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002



I, David N. Weidman, certify that:



1. I have reviewed this quarterly report on
    Form 10-Q
    of Celanese Holdings LLC;



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;



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;



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))
    and internal control over financial reporting (as defined in
    Exchange Act Rules 13a-15(f) and 15d-15(f))  for the registrant
    and we have:



(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;



(b) designed such internal control over financial
    reporting, or caused such internal control over financial
    reporting to be designed under our supervision, to provide
    reasonable assurance regarding the reliability of financial
    reporting and the preparation of financial statements for
    external purposes in accordance with generally accepted
    accounting principles;



(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



(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



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):



(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



(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.



/s/  David
    N. Weidman



David N. Weidman

Chief Executive Officer and President



Date: May 9, 2007

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