Exhibit 10.21
                                                                   -------------




December 9, 2003




Myron Levy
807 Bent Creek Drive
Lititz, PA 17543

Dear Mr. Levy:

Re:   Employment Agreement dated 29 July 2002 between
      Herley Industries, Inc. and Myron Levy (the "Employment Agreement")

Dear Mr. Blatt:

               The  following  will set forth  our  mutual  agreement  as to the
modification of the Employment Agreement:

Section 2(b) is replaced entirely by the following:

(b) Employment  Term. The Employment Term shall commence as of July 29, 2002 and
shall  terminate on December 31, 2007,  provided that the Employment  Term shall
extend for  additional  one-year  periods  annually  each January 1, unless this
agreement is terminated  under the provisions of Section 10 below.  In no event,
however, shall the Employment Term extend beyond December 31, 2015.

In  all  other  respects,  the  Employment  Agreement  is  hereby  ratified  and
confirmed.

If you agree with all of the above,  would you please  sign and return a copy of
this letter whereupon the same shall constitute a binding agreement between us.



                                            By:   /S/   John M. Kelley
                                                ----------------------
                                                   John M. Kelley
                                                   President

ACCEPTED AND AGREED:

   /S/   Myron Levy
- -------------------
   Myron Levy