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                                                                    EXHIBIT 99.1

                                  CERTIFICATION

I, John A. Schofield, Chairman of the Board, President and Chief Executive
Officer of Advanced Fibre Communications, Inc., or AFC, certify that:

     1. I have reviewed this annual report on Form 10-K of AFC;

     2. Based on my knowledge, this annual 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 annual
report;

     3. Based on my knowledge, the financial statements, and other financial
information included in this annual report, fairly present in all material
respects the financial condition, results of operations and cash flows of AFC as
of, and for, the periods presented in this annual report;

     4. AFC's other certifying officer and I are responsible for establishing
and maintaining disclosure controls and procedures (as defined in Exchange Act
Rules 13a-14 and 15d-14) for AFC and we have:

     (a) designed such disclosure controls and procedures to ensure that
     material information relating to AFC, including its consolidated
     subsidiaries, is made known to us by others within those entities,
     particularly during the period in which this annual report is being
     prepared;

     (b) evaluated the effectiveness of AFC's disclosure controls and procedures
     as of a date within 90 days prior to the filing date of this annual report
     (the "Evaluation Date"); and

     (c) presented in this annual report our conclusion about the effectiveness
     of the disclosure controls and procedures based on our evaluation as of the
     Evaluation Date;

     5. AFC's other certifying officer and I have disclosed, based on our most
recent evaluation, to AFC's auditors and the audit committee of AFC's board of
directors (or persons performing the equivalent function):

     (a) all significant deficiencies in the design or operation of internal
     controls which could adversely affect AFC's ability to record, process,
     summarize and report financial data and have identified for AFC's auditors
     any material weaknesses in internal controls; and

     (b) any fraud, whether or not material, that involves management or other
     employees who have a significant role in AFC's internal controls; and

     6. AFC's other certifying officer and I have indicated in this annual
report whether or not there were significant changes in internal controls or in
other factors that could significantly affect internal controls subsequent to
the date of our most recent evaluation, including any corrective actions with
regard to significant deficiencies and material weaknesses.


Date: March 18, 2003            By: /s/ John A. Schofield
                                    --------------------------------------------
                                    Name:  John A. Schofield
                                    Title: Chairman of the Board,
                                           President and Chief Executive Officer
                                           (Duly Authorized Signatory and
                                           Chief Executive Officer)


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