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                                                           Exhibit 10.55

                  AMENDMENT NUMBER FOUR TO EMPLOYMENT AGREEMENT

         THIS AMENDMENT NUMBER FOUR TO EMPLOYMENT AGREEMENT (this "Amendment")
is effective as of _______________, 1999, between STAR TELECOMMUNICATIONS, INC.,
a Delaware corporation ("STAR"), and MARY CASEY ("EXECUTIVE").

         RECITALS:

         A. STAR (or STAR Vending, Inc., a Nevada corporation, predecessor in
interest to STAR) and Executive are parties to that certain Employment Agreement
effective as of July 14, 1995, as amended by that certain Amendment Number One
to Employment Agreement effective as of January 1, 1996, that certain Amendment
Number Two to Employment Agreement effective as of July 15, 1996, and that
certain Amendment Number Three to Employment Agreement effective as of July 1,
1997 (collectively, the "Employment Agreement"), pursuant to which Executive is
employed by STAR.

         B. The parties desire to modify certain terms of the Employment
Agreement, as set forth in this Amendment.

         AGREEMENTS:

         NOW, THEREFORE, the parties agree to amend the Employment Agreement as
follows:

         1. DEFINED TERMS. Capitalized terms used in this Amendment and not
otherwise defined shall have the meanings ascribed to them in the Employment
Agreement. From and after the date hereof, the term "Agreement" as used in the
Employment Agreement will mean the Employment Agreement as amended by this
Amendment, unless and until such Employment Agreement may again be amended.

         2. AMENDMENT OF SECTION 7. Section 7 of the Employment Agreement is
hereby amended to read in its entirety as follows:

                  "7. TERMINATION.

                           7.1 METHODS OF TERMINATION. This Agreement and the
                           employment of Executive may be terminated at any
                           time:

                                    A. By mutual agreement of the parties.

                                    B. By STAR if Executive dies or becomes
                                    physically or mentally disabled (the term
                                    "disabled" shall mean any mental or physical
                                    illness or disability that renders the
                                    Executive unable to perform the essential
                                    functions of her position, after reasonable
                                    accommodation of such disability by STAR).


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                                    C. By STAR, for cause, if Executive (a) has
                                    committed any material act of dishonesty,
                                    fraud or misrepresentation or any act of
                                    moral turpitude; (b) is in default in the
                                    performance of Executive's material
                                    obligations, services or duties under this
                                    Agreement; or (c) has failed to execute
                                    specific instructions from STAR's Board of
                                    Directors or executive officers, which
                                    failure is not corrected by Executive after
                                    reasonable notice from STAR.

                                    D. By STAR, without cause, at any time
                                    during the term of this Agreement.

                                    E. By the Executive if STAR is in default of
                                    its material obligations or duties under
                                    this Agreement.

                                    F. By the Executive, without cause, at any
                                    time during the term of this Agreement.

                           7.2 CONSEQUENCES OF TERMINATION. Executive shall be
                           entitled to the following compensation in the event
                           of a termination:

                                    A. In the event of any termination under
                                    Sections 7.1A, 7.1B, 7.1C, or 7.1F,
                                    Executive (or, in the event of Executive's
                                    death, her estate) shall be entitled to
                                    receive compensation accrued and payable to
                                    her as of the date of termination or death,
                                    and all other amounts payable under this
                                    Agreement shall thereupon cease.

                                    B. In the event of any termination under
                                    Section 7.1D or Section 7.1E, then Executive
                                    shall continue to receive the compensation
                                    provided in this Agreement until the
                                    expiration of this Agreement. Any amounts
                                    earned by her (other than through her
                                    personal investment activities) prior to
                                    such expiration by virtue of other
                                    employment shall be deducted from amounts to
                                    which she is entitled under this Agreement.

                           7.3 IRC VIOLATIONS. Any provision in this Agreement
                           to the contrary notwithstanding, in no event will
                           Executive receive a payment which would trigger the
                           excise taxes and disallowance of deductions
                           contemplated by Sections 280G and 4999 of the
                           Internal Revenue Code of 1986, as amended (the
                           "Code"). In the event that any amount calculated
                           would result in such a payment, such amount shall be
                           reduced to the largest amount that would not result
                           in such a payment. This reduction shall apply to any
                           and all compensation, including compensation pursuant
                           to stock option grants governed by separate agreement
                           between STAR and Executive. If, at the time of any
                           such payment, no stock of STAR is readily tradeable
                           on an established securities market or otherwise,
                           then STAR agrees to use its best efforts to cause
                           such payment to meet the exemption set forth in
                           Sections 280G(b)(5)(A)(ii) and (B) of the Code, so
                           that no reduction will be required under this
                           Agreement."


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         3. CONFIRMATION. Except as specifically amended by this Amendment, the
Employment Agreement will continue unchanged, and the terms and conditions of
the Employment Agreement, as amended by this Amendment, are ratified and
confirmed.

         IN WITNESS WHEREOF, the parties have executed this Amendment effective
as of the date first set forth above.

                                       "STAR"

                                       STAR TELECOMMUNICATIONS, INC.,
                                       a Delaware corporation

                                       By:
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                                             Christopher E. Edgecomb,
                                             Chief Executive Officer

                                       "EXECUTIVE"

                                          --------------------------------------
                                       Mary Casey

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