EXHIBIT 4.15
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                                 PROMISSORY NOTE

$1,000,000.00                                                      June 18, 1998

                  FOR VALUE  RECEIVED,  Executive  TeleCard,  Ltd.,  a  Delaware
corporation  (the "Maker"),  promises to pay to the order of SEYMOUR GORDON,  or
assigns (the  "Holder"),  at 3 Hawthorne  Lane,  Lawrence,  NY 11559, or at such
other place as the Holder of this Note may from time to time  designate,  on the
date that is eighteen (18) months after the date hereof (the  "Maturity  Date"),
the  principal  amount of One Million  Dollars  ($1,000,000.00),  together  with
interest on the unpaid  principal  amount hereof from the date hereof until paid
in full, said interest to be due and payable on the Maturity Date, at a rate per
annum equal to eight and seven eighths percent (8 7/8%),  simple  interest.  All
payments  hereunder  shall be made in  lawful  money  of the  United  States  of
America, without offset.

                  In the event that the Holder  has the  opportunity  to convert
the principal amount of this Promissory Note to convertible shares of the Maker,
then the accrued  interest  shall be due and payable at the time of the issuance
of such  convertible  shares,  or on the Maturity Date of the  Promissory  Note,
whichever is earlier. In the event that the Holder has a right of conversion and
elects not to convert,  then the  interest  hereunder  shall be payable  monthly
until maturity.

                  The indebtedness evidenced by this Note shall be junior to all
indebtedness incurred by Maker to IDT Corporation.

                  The  unpaid  principal  amount of this Note may be  prepaid in
whole  or in  part  at any  time or  times  without  premium  or  penalty.  Each
prepayment  shall be  applied  first to the  payment of all  interest  and other
amounts accrued hereunder on the date of any such prepayment, and the balance of
any such prepayment shall be applied to the principal amount hereof.

                  The  occurrence  of any  one or more  of the  following  shall
constitute an event of default ("Event of Default") hereunder:

                  (1) Failure to pay, when due, the principal,  any interest, or
         any other sum payable  hereunder  (whether upon maturity  hereof,  upon
         prepayment date, upon acceleration, or otherwise).

                  (2) Failure to pay,  when due,  whether  upon  maturity,  upon
         acceleration, or otherwise, of indebtedness other than this Note in the
         amount of $67,000 or more;




                  (3) The  failure  of the Maker  generally  to pay its debts as
         such debts  become due,  the  admission  by the Maker in writing of its
         inability  to pay its debts as such debts  become due, or the making by
         Maker of any general assignment for the benefit of creditors;

                  (4) The commencement by the Maker of any case, proceeding,  or
         other   action   seeking   reorganization,   arrangement,   adjustment,
         liquidation,  dissolution,  or  composition  of its debts under any law
         relating to bankruptcy,  insolvency,  or  reorganization,  or relief of
         debtors, or seeking appointment of a receiver,  trustee,  custodian, or
         other similar official for all or any substantial part of its property;

                  (5) The commencement of any case, proceeding,  or other action
         against Maker seeking to have any order for relief entered  against the
         Maker as debtor, or seeking  reorganization,  arrangement,  adjustment,
         liquidation,  dissolution,  or  composition  of the  Maker or its debts
         under any law relating to bankruptcy,  insolvency,  reorganization,  or
         relief of  debtors,  or seeking  appointment  of a  receiver,  trustee,
         custodian,  or other  similar  official for the Maker or for all or any
         substantial part of the property of the Maker, and (i) the Maker shall,
         by any act or  omission,  indicate  its  consent  to,  approval  of, or
         acquiescence  in such case,  proceeding  or action;  or (ii) such case,
         proceeding, or action results in the entry of an order for relief which
         is not fully stayed within seven business days after the entry thereof.

                  Upon the  occurrence  of any such Event of Default  hereunder,
the entire principal amount hereof, and all accrued and unpaid interest thereof,
shall be accelerated, and shall be immediately due and payable, at the option of
the  Holder  without  demand or  notice,  and in  addition  thereto,  and not in
substitution  therefor, the Holder shall be entitled to exercise any one or more
of the rights and remedies  provided by applicable law. Failure to exercise said
option or to pursue such other  remedies  shall not  constitute a waiver of such
option or such other remedies or of the right to exercise any of the same in the
event of any subsequent Event of Default hereunder.

                  In the event that the principal amount hereof, any interest or
any other sum due  hereunder is not paid when due and payable,  the whole of the
unpaid principal amount evidenced hereby and all unpaid accrued interest thereon
shall  from the date when such  payment  was due and  payable  until the date of
payment in full  thereof,  bear  interest  at the higher of the rate of interest
hereinbefore provided for or the rate of thirteen percent (13%) per annum, which
rate, if applicable,  shall commence,  without notice, immediately upon the date
when said payment was due and payable.



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                  The Maker  promises to pay all costs and expenses  (including,
without  limitation,  attorneys' fees and disbursements)  incurred in connection
with the collection thereof.

                  Any payment on this Note  coming due on a Saturday,  a Sunday,
or a day which is a legal  holiday in the place at which a payment is to be made
hereunder  shall be made on the next  succeeding  day which is a business day in
such place,  and any such  extension of the time of payment shall be included in
the computation of interest hereunder.

                  Whenever used herein,  the words "Maker" and "Holder" shall be
deemed to include their respective successors and assigns.

                  This Note  shall be  governed  by and  construed  under and in
accordance  with the laws of the state of New York (but not including the choice
of law rules thereof).

                  IN WITNESS  WHEREOF,  the  undersigned  has duly executed this
Note, or have caused this Note to be duly  executed on their  behalf,  as of the
day and year first hereinabove set forth.


[SEAL]                                   EXECUTIVE TELECARD, LTD.


                                         By:                                    
                                            ------------------------------------
                                            Christopher J. Vizas
                                            Chairman and Chief Executive Officer


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