EX-99. CERT
CERTIFICATION PURSUANT TO SECTION 302
OF THE SARBANES-OXLEY ACT OF 2002
I, Robert C. Doll, Jr., Chief Executive Officer of CMA Tax-Exempt Fund and
Master Tax-Exempt Trust, certify that:
1. I have reviewed this report on Form N-CSR of CMA Tax-Exempt Fund and
Master Tax-Exempt Trust;
2. Based on my knowledge, this 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
report;
3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material
respects the financial condition, results of operations, changes in net
assets, and cash flows (if the financial statements are required to
include a statement of cash flows) of the registrants as of, and for, the
periods presented in this report;
4. The registrants' other certifying officer(s) and I are responsible for
establishing and maintaining disclosure controls and procedures (as
defined in Rule 30a-3(c) under the Investment Company Act of 1940) and
internal control over financial reporting (as defined in Rule 30a-3(d)
under the Investment Company Act of 1940) for the registrants and 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 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 registrants' disclosure controls and
procedures and presented in this report our conclusions about the
effectiveness of the disclosure controls and procedures, as of a date
within 90 days prior to the filing date of this report based on such
evaluation; and
d) disclosed in this report any change in the registrants' internal control
over financial reporting that occurred during the second fiscal quarter of
the period covered by this report that has materially affected, or is
reasonably likely to materially affect, the registrants' internal control
over financial reporting; and
5. The registrants' other certifying officer(s) and I have disclosed to the
registrants' auditors and the audit committees of the registrants' boards
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 registrants' internal control
over financial reporting.
Date: May 22, 2006
/s/ Robert C. Doll, Jr.
-------------------------
Robert C. Doll, Jr.,
Chief Executive Officer of
CMA Tax-Exempt Fund and
Master Tax-Exempt Trust
EX-99. CERT
CERTIFICATION PURSUANT TO SECTION 302
OF THE SARBANES-OXLEY ACT OF 2002
I, Donald C. Burke, Chief Financial Officer of CMA Tax-Exempt Fund and Master
Tax-Exempt Trust, certify that:
1. I have reviewed this report on Form N-CSR of CMA Tax-Exempt Fund and
Master Tax-Exempt Trust;
2. Based on my knowledge, this 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
report;
3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material
respects the financial condition, results of operations, changes in net
assets, and cash flows (if the financial statements are required to
include a statement of cash flows) of the registrants as of, and for, the
periods presented in this report;
4. The registrants' other certifying officer(s) and I are responsible for
establishing and maintaining disclosure controls and procedures (as
defined in Rule 30a-3(c) under the Investment Company Act of 1940) and
internal control over financial reporting (as defined in Rule 30a-3(d)
under the Investment Company Act of 1940) for the registrants and 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 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 registrants' disclosure controls and
procedures and presented in this report our conclusions about the
effectiveness of the disclosure controls and procedures, as of a date
within 90 days prior to the filing date of this report based on such
evaluation; and
d) disclosed in this report any change in the registrants' internal control
over financial reporting that occurred during the second fiscal quarter of
the period covered by this report that has materially affected, or is
reasonably likely to materially affect, the registrants' internal control
over financial reporting; and
5. The registrants' other certifying officer(s) and I have disclosed to the
registrants' auditors and the audit committees of the registrants' boards
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 registrants' internal control
over financial reporting.
Date: May 22, 2006
/s/ Donald C. Burke
--------------------
Donald C. Burke,
Chief Financial Officer of
CMA Tax-Exempt Fund and
Master Tax-Exempt Trust