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                                                                    EXHIBIT 31.1

                    CERTIFICATION OF CHIEF EXECUTIVE OFFICER

I, D. Gregory Smith, certify that--

         1. I have reviewed this Quarterly Report on Form 10-Q of Z-Tel
Technologies, Inc.;

         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 in order
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 and cash flows of the registrant as
of, and for, the periods presented in this report;

         4. The registrant's other certifying officers 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--

                  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) Evaluated the effectiveness of the registrant's disclosure
controls and procedures and presented in this report our conclusions about the
effectiveness of the disclosure controls and procedures as the end of the period
covered by this report based on such evaluation; and

                  c) Disclosed in this any change in the registrant's internal
control over financial reporting 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 officers 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 the
registrant's board of directors (or persons fulfilling the equivalent
function)--

                  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.

Date:  August 12, 2004

                                          /s/ D. GREGORY SMITH
                                          -------------------------------------
                                          D. Gregory Smith
                                          Chief Executive Officer

         A signed original of this written statement has been provided to Z-Tel
Technologies, Inc. and will be retained by the Z-Tel Technologies, Inc. and
furnished to the Securities and Exchange Commission or its staff upon request