UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                  SCHEDULE 13D

                    Under the Securities Exchange Act of 1934

                                 RADVISION LTD.
                                 --------------
                                (Name of Issuer)

                 Ordinary Shares, par value NIS 0.10 per share
                 ---------------------------------------------
                         (Title of Class of Securities)

                                   M8186910 5
                                   ----------
                                 (CUSIP Number)

                               Steven J. Glusband
                          Carter Ledyard & Milburn LLP
                     2 Wall Street, New York, New York 10005
                                 (212) 732-3200
            --------------------------------------------------------
            (Name, Address and Telephone Number of Person Authorized
                     to Receive Notices and Communications)

                                 August 4, 2008
             -------------------------------------------------------
             (Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report
the acquisition that is the subject of this Schedule 13D, and is filing this
schedule because of Rule 13d-1(e), Rule 13d-1(f) or Rule 13d-1(g), check the
following box [ ]

Note: Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See ss. 240.13d-7 for other
parties to whom copies are to be sent.

*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter
disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).










                                Explanatory Note
                                ----------------

The Reporting Person previously filed a statement on Schedule 13G/A pursuant to
the provisions of Rule 13d-1(d) under the Securities Exchange Act of 1934, as
amended, to report his beneficial ownership of the Issuer's ordinary shares
(File No. 005-58761).


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CUSIP No.  M8186910 5


1   NAME OF REPORTING PERSON: Zohar Zisapel

    I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY): Not applicable.

2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP:                    (a) [ ]
                                                                         (b) [X]

3   SEC USE ONLY

4   SOURCE OF FUNDS: PF

5   CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO
    ITEMS 2(d) or 2(e):                                                      [ ]

6   CITIZENSHIP OR PLACE OF ORGANIZATION: Israel

NUMBER OF         7     SOLE VOTING POWER:  3,042,119 Ordinary Shares*
SHARES
BENEFICIALLY      8     SHARED VOTING POWER:  187,213 Ordinary Shares
OWNED BY EACH
REPORTING         9     SOLE DISPOSITIVE POWER:  3,042,119 Ordinary Shares*
PERSON WITH
                  10    SHARED DISPOSITIVE POWER:  187,213 Ordinary Shares

11  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 3,229,332
    Ordinary Shares*

12  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES [ ]

13  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):15.93%**

14  TYPE OF REPORTING PERSON:  HC

-----------------
*    Includes  93,750  Ordinary  Shares  issuable  upon the  exercise of options
     granted to the  Reporting  Person  exercisable  as of August  24,  2008 and
     within 60 days thereafter.

**   Based on 20,266,537 Ordinary Shares that the Issuer advised were issued and
     outstanding  (which  excludes  2,249,686  Ordinary  Shares held as treasury
     stock) as of August 24, 2008.


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Item 1. Security and Issuer
        -------------------

         This Statement on Schedule 13D relates to the Ordinary Shares, par
value NIS 0.10 per share (the "Ordinary Shares"), of RADVISION Ltd. (the
"Issuer"), an Israeli company whose principal executive offices are located at
24 Raoul Wallenberg Street, Tel Aviv 69719, Israel.

Item 2. Identity and Background
        -----------------------

         Mr. Zohar Zisapel, a citizen of Israel, serves as chairman of the board
of directors of the Issuer. Mr. Zisapel is a founder and director of several
other companies which, together with the Issuer and its other subsidiaries and
affiliates, are known as the RAD-BYNET group. Mr. Zisapel's business address is
24 Raoul Wallenberg Street, Tel Aviv 69719, Israel.

         During the last five years, Mr. Zisapel has not been convicted in any
criminal proceeding (excluding traffic violations or similar misdemeanors), nor
has he been a party to a civil proceeding of a judicial or administrative body
of competent jurisdiction as a result of which proceeding he was or is subject
to a judgment, decree or final order either enjoining future violations of, or
prohibiting or mandating activities subject to, United States federal or state
securities laws, or finding any violation with respect to such laws.

Item 3. Source and Amount of Funds or Other Consideration.
        --------------------------------------------------

         During the last 60 days, Mr. Zisapel has purchased an aggregate of
405,596 Ordinary Shares of the Issuer in a series of transactions. The aggregate
purchase price for such 405,596 Ordinary Shares was approximately $2,661,902,
all of which amount was paid by the Reporting Person from his personal funds.

Item 4. Purpose of Transaction.
        -----------------------

         The 405,596 Ordinary Shares purchased by Mr. Zisapel during the last 60
days were purchased for investment purposes.  Mr. Zisapel currently does not
have any plan or proposal, which relates to or would result in:

          (a) the  acquisition  by any person of  additional  securities  of the
     Issuer, or the disposition of securities of the Issuer;

          (b)  an  extraordinary  corporate  transaction,   such  as  a  merger,
     reorganization,  or  liquidation,  involving  the  Issuer  or  any  of  its
     subsidiaries;

          (c) a sale or  transfer  of a  material  amount  of the  assets of the
     Issuer or any of its subsidiaries;

          (d) any change in the present  board of directors or management of the
     Issuer,  including  any plan or  proposal  to change  the number or term of
     directors or to fill any existing vacancies on the board;

          (e) any  material  change in the  present  capitalization  or dividend
     policy of the Issuer;

          (f) any other  material  change in the Issuer's  business or corporate
     structure;

          (g) changes in the Issuer's  charter or by-laws or other actions which
     may impede the acquisition of control of the Issuer by any person;

          (h) a class of securities of the Issuer being delisted from a national
     securities  exchange  or  ceasing  to  be  authorized  to be  quoted  in an
     inter-dealer   quotation  system  of  a  registered   national   securities
     association;



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          (i) a class of equity  securities of the Issuer becoming  eligible for
     termination of registration  pursuant to Section 12(g)(4) of the Securities
     Exchange Act of 1934; or

          (j) any action similar to any of those enumerated above.

Item 5. Interest in Securities of the Issuer.
        -------------------------------------

         (a) Mr. Zisapel is the beneficial owner of 3,229,332 Ordinary Shares of
the Issuer, which constitute approximately 15.93% of the 20,266,537 Ordinary
Shares of the Issuer that the Issuer advised were issued and outstanding (which
excludes 2,249,686 Ordinary Shares held as treasury stock) as of August 24,
2008. Of such shares, (i) 2,331,057 Ordinary Shares were held of record by the
Reporting Person; (ii) 93,750 Ordinary Shares were issuable upon the exercise of
options granted to the Reporting Person exercisable as of August 24, 2008 or
within 60 days thereafter; (iii) 306,456 Ordinary Shares were held of record by
Lomsha Ltd., an Israeli company controlled by the Reporting Person; (iv) 310,856
Ordinary Shares were held of record by Michael and Klil Holdings (93) Ltd., an
Israeli company controlled by the Reporting Person; and (v) 187,213 Ordinary
Shares were held of record by RAD Data Communications Ltd., an Israeli company.
The Reporting Person is a principal shareholder and Chairman of the Board of
Directors of RAD Data Communications Ltd. The Reporting Person and his brother
Mr. Yehuda Zisapel have shared voting and dispositive power with respect to the
shares held by RAD Data Communications Ltd.

         (b) Mr. Zohar Zisapel has sole power to vote or direct the vote and the
sole power to dispose or direct the disposition of 2,331,057 Ordinary Shares of
the Issuer held by him directly.

             Mr. Zohar Zisapel has sole power to vote or direct the vote
and the sole power to dispose or direct the disposition of 93,750 Ordinary
Shares of the Issuer underlying the options held by him directly that are
exercisable as of August 24, 2008 or within 60 days thereafter.

             Mr. Zohar Zisapel has sole power to vote or direct the vote
and the sole power to dispose or direct the disposition of 306,456 Ordinary
Shares of the Issuer held of record by Lomsha Ltd.

             Mr. Zohar Zisapel has sole power to vote or direct the vote
and the sole power to dispose or direct the disposition of 310,856 Ordinary
Shares of the Issuer held of record by Michael and Klil Holdings (93) Ltd.

             Mr. Zohar Zisapel and his brother Mr. Yehuda Zisapel have
shared power to vote or direct the vote and the shared power to dispose or
direct the disposition of the 187,213 Ordinary Shares of the Issuer held of
record by RAD Data Communications Ltd.

         (c) The following table sets forth all the transactions in the Ordinary
Shares of the Issuer effected by Mr. Zohar Zisapel during the past sixty days.
All such transactions were open market purchases effected on the NASDAQ Global
Market.



                                    Number of Ordinary
          Date of Purchase           Shares Purchased            Price Per Share
          ----------------           ----------------            ---------------
             8/04/2008                    51,250                      $5.84
             8/06/2008                    21,200                      $6.18
             8/07/2008                    17,121                      $6.35
             8/08/2008                    20,714                      $6.50
             8/11/2008                    57,710                      $6.81
             8/12/2008                    26,986                      $6.86
             8/13/2008                    10,591                      $6.80
             8/14/2008                    34,910                      $6.91
             8/15/2008                     8,604                      $6.91
             8/18/2008                    24,524                      $6.76
             8/19/2008                    43,936                      $6.63
             8/20/2008                    65,990                      $6.58
             8/21/2008                    16,900                      $6.63
             8/22/2008                     5,160                      $6.63



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         Except for such transactions, Mr. Zohar Zisapel has not effected any
transactions in the Ordinary Shares of the Issuer during the past sixty days.

         (d) No person other than Mr. Zohar Zisapel has the right to receive or
the power to direct the receipt of dividends from, or the proceeds from the sale
of, the shares reported above in this Item 5(c).

         (e) Not applicable.

Item 6. Contracts, Arrangements, Understandings or Relationships with Respect to
        Securities of the Issuer
        ------------------------

         None.

Item 7. Material to be Filed as Exhibits.
        ---------------------------------

         None.





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                                    SIGNATURE


         After reasonable inquiry and to the best of our knowledge and belief,
we certify that the information set forth in this statement is true, complete
and correct.


         Date: August 25, 2008



                                            /s/Zohar Zisapel
                                            ----------------
                                            Zohar Zisapel





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