COMMON STOCK AND WARRANT PURCHASE AGREEMENT


         THIS  COMMON  STOCK  AND  WARRANT  PURCHASE  AGREEMENT  is  dated as of
September  16,  2003  (this  "Purchase  Agreement"),  by and  between  XYBERNAUT
CORPORATION,  a Delaware  corporation,  having its  principal  place of business
located at 12701 Fair Lakes  Circle,  Suite 550,  Fairfax,  Virginia  22033 (the
"Company"),  and ESSEX  TRADING LTD., a company  incorporated  under the laws of
Navis,  having its principal place of business  located at Fitzroy Mews 5, Suite
No. 7, London, England (the "Investor").

                               W I T N E S S E T H

         WHEREAS,  the Company wishes to sell to the Investor,  and the Investor
is willing to purchase from the Company, subject to the terms and conditions set
forth herein,  $2,000,000  of shares of common  stock,  par value $.01 per share
(the "Common Stock"), of the Company.

         NOW, THEREFORE, for and in consideration of the premises and the mutual
agreement  contained herein and for other good and valuable  consideration,  the
receipt and  sufficiency  of which are hereby  acknowledged,  the parties hereto
agree as follows:

         1. PURCHASE AND SALE; MUTUAL  DELIVERIES.  (a) Upon the following terms
and  conditions,  the  Company  shall  issue  and sell to the  Investor  and the
Investor  shall  purchase from the Company that number of shares of Common Stock
equal to $2,000,000 (the "Aggregate  Amount")  divided by $1.25 cents per share,
which price is based upon an approximately 18% discount to the closing bid price
of the Common  Stock on the date hereof (the  "Purchase  Price"),  resulting  in
1,600,000  shares (the  "Shares")  to be issued upon the payment of the Purchase
Price. Upon receipt of the Purchase Price,  which payment and receipt must occur
within twenty (20) business days from the date hereof, the Company shall deliver
to the  Investor  one or more  certificates  representing  the  Shares,  bearing
substantially the following legend:

                  THE SECURITIES REPRESENTED HEREBY (THE "SECURITIES") HAVE NOT
                  BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED
                  (THE "SECURITIES ACT"), OR THE SECURITIES LAWS OF ANY STATE
                  AND MAY NOT BE SOLD OR OFFERED FOR SALE IN THE ABSENCE OF AN
                  EFFECTIVE REGISTRATION STATEMENT FOR THE SECURITIES OR AN
                  OPINION OF COUNSEL OR OTHER EVIDENCE ACCEPTABLE TO THE
                  CORPORATION THAT SUCH REGISTRATION IS NOT REQUIRED.


            (b) The Company  shall also deliver,  or cause to be delivered,  the
original or execution copies of this Purchase Agreement.





         2. REPRESENTATIONS  AND  WARRANTIES  OF  THE  COMPANY.    The   Company
represents and warrants to the Investor that:

            (a) The Company has the corporate  power and authority to enter into
this Purchase Agreement, and to perform its obligations hereunder. The execution
and delivery by the Company of this Purchase  Agreement and the  consummation by
the Company of the transactions contemplated hereby have been duly authorized by
all  necessary  corporate  action  on the  part of the  Company.  This  Purchase
Agreement has been duly executed and delivered by the Company and constitute the
valid and binding obligation of the Company enforceable against it in accordance
with  their  respective  terms,   subject  to  the  effects  of  any  applicable
bankruptcy,  insolvency,  reorganization,  moratorium or similar laws  affecting
creditors' rights generally and to general equitable principles.

            (b)  Except  as set  forth  in the  SEC  Documents  (as  hereinafter
defined),  there is no pending, or to the knowledge of the Company,  threatened,
judicial,   administrative  or  arbitral  action,  claim,  suit,  proceeding  or
investigation which might affect the validity or enforceability of this Purchase
Agreement or which involves the Company and which if adversely determined, could
reasonably be expected to have a material  adverse effect on the Company and its
subsidiaries taken as a whole.

            (c) No consent or approval of, or exemption by, or filing with,  any
party or governmental or public body or authority is required in connection with
the execution,  delivery and  performance  under this Purchase  Agreement or the
taking of any action contemplated hereunder or thereunder.

            (d) The Company has been duly organized and is validly existing as a
corporation  in  good  standing  under  the  laws  of  the  jurisdiction  of its
incorporation.

            (e) The execution, delivery and performance of this Agreement by the
Company, and the consummation of the transactions  contemplated hereby, will not
(i) violate any provision of the Company's  articles of incorporation or bylaws,
(ii)  violate,  conflict  with or result  in the  breach of any of the terms of,
result in a material  modification of the effect of,  otherwise,  give any other
contracting party the right to terminate, or constitute (or with notice or lapse
of time or both  constitute) a default under, any contract or other agreement to
which  the  Company  is a party  or by or to  which  the  Company  or any of the
Company's assets or properties may be bound or subject, (iii) violate any order,
judgment,  injunction,  award or decree of any court, arbitrator or governmental
or  regulatory  body by which the Company,  or the assets or  properties  of the
Company are bound and (iv) to the Company's knowledge,  violate any statute, law
or regulation.




                                      -2-



         3. REPRESENTATIONS AND WARRANTIES OF THE INVESTOR.  The Investor hereby
represents and warrants to the Company that:

            (a) The Investor has the corporate power and authority to enter into
this Purchase Agreement and to perform its obligations hereunder.  The execution
and delivery by the Investor of this Purchase Agreement, and the consummation by
the Investor of the transactions  contemplated hereby, have been duly authorized
by all necessary  corporate  action on the part of the  Investor.  This Purchase
Agreement has been duly  executed and  delivered by the Investor and  constitute
the valid and binding  obligation  of the  Investor,  enforceable  against it in
accordance with their respective terms, subject to the effects of any applicable
bankruptcy,  insolvency,  reorganization,  moratorium or similar laws  affecting
creditors' rights generally and to general equitable principles.

            (b) The execution,  delivery and performance by the Investor of this
Purchase  Agreement,  and  the  consummation  of the  transactions  contemplated
hereby,  do not and will not breach or constitute a default under any applicable
law  or  regulation  or of any  agreement,  judgment,  order,  decree  or  other
instrument binding on the Investor.

            (c) The Investor has such knowledge and prior substantial investment
experience in financial and business matters, including investment in non-listed
and  non-registered  securities,  and has  had the  opportunity  to  engage  the
services  of an  investment  advisor,  attorney  or  accountant  to read the SEC
Documents  and to evaluate the merits and risks of investment in the Company and
the Securities.

            (d) The Investor is an "accredited investor" as that term is defined
in Rule 501(a) of Regulation D promulgated  under the Securities Act of 1933, as
amended (the "Securities Act").

            (e) The  Investor is not a "U.S.  Person" as that term is defined in
Regulation S promulgated under the Securities Act.

            (f) The Investor is acquiring the Shares,  the Investor Warrants (as
defined in Section  4(d)) and the shares of Common Stock  issuable upon exercise
of the Investor  Warrants (the "Warrant  Shares")  solely for the Investor's own
account for investment  and not with a view to or for sale in connection  with a
distribution  of any of the Shares or the Warrant  Shares (the Shares,  Warrants
and Warrant Shares collectively, the "Securities");

            (g) The  Investor  does not  have a  present  intention  to sell the
Securities, nor a present arrangement or intention to effect any distribution of
any of the  Securities  to or  through  any  person or entity  for  purposes  of
selling, offering, distributing or otherwise disposing of any of the Securities;

            (h) The Investor  may be required to bear the  economic  risk of the
investment indefinitely because none of the Securities may be sold, hypothecated
or otherwise disposed of unless subsequently registered under the Securities Act
and  applicable  state  securities  laws or an exemption  from  registration  is
available.  Any resale of any of the Securities can be made only



                                      -3-


pursuant  to (i) a  registration  statement  under the  Securities  Act which is
effective and current at the time of sale or (ii) a specific  exemption from the
registration requirements of the Securities Act. In claiming any such exemption,
the Investor will,  prior to any offer or sale or distribution of any Securities
advise the Company  and,  if  requested,  provide  the Company  with a favorable
written opinion of counsel, in form and substance satisfactory to counsel to the
Company,  as to the  applicability  of such  exemption to the  proposed  sale or
distribution;

            (i) The Investor understands that the exemption afforded by Rule 144
promulgated by the Securities and Exchange  Commission  under the Securities Act
("Rule  144") will not become  available  for at least one year from the date of
payment  for the  Securities  and any sales in  reliance  on Rule  144,  if then
available,  can be made only in accordance with the terms and conditions of that
rule,  including,  among other things,  a  requirement  that the Company then be
subject  to,  and  current,  in  its  periodic  filing  requirements  under  the
Securities  Exchange Act of 1934, as amended (the  "Exchange  Act"),  and, among
other  things,  a limitation on the amount of shares of Common Stock that may be
sold in  specified  time  periods  and the manner in which the sale can be made;
that,  while the Company's Common Stock is registered under the Exchange Act and
the Company is presently subject to the periodic  reporting  requirements of the
Exchange Act,  there can be no assurance that the Company will remain subject to
such reporting  obligations or current in its filing  obligations;  and that, in
case Rule 144 is not applicable to a disposition of the  Securities,  compliance
with the  registration  provisions of the Securities Act or some other exemption
from such registration provisions will be required; and

            (j) The Investor  understands  that  legends  shall be placed on the
certificates  evidencing the  Securities to the effect that the Securities  have
not been registered under the Securities Act or applicable state securities laws
and  appropriate  notations  thereof will be made in the Company's  stock books.
Stop  transfer  instructions  will be  placed  with  the  transfer  agent of the
securities constituting the Common Stock.

         4.  COVENANTS OF THE COMPANY.  (a) The Company  covenants and agrees to
enter into a registration  rights  agreement  governing the  registration of the
Securities with the Investor dated as of the date hereof.

            (b) Current  Public  Information.  The Company has furnished or made
available  to  the  Investor  true  and  correct  copies  of  all   registration
statements,  reports  and  documents,  including  proxy  statements  (other than
preliminary proxy statements), filed with the Securities and Exchange Commission
(the "SEC") by or with respect to the Company since  December 31, 2002 and prior
to the date of this  Agreement,  pursuant to the  Securities Act or the Exchange
Act (collectively,  the "SEC Documents"). The SEC Documents are the only filings
made by or with  respect to the Company  since  December  31,  2002  pursuant to
Sections  13(a),  13(c),  14 and 15(d) of the  Exchange  Act or  pursuant to the
Securities Act. The Company has filed all reports,  schedules, forms, statements
and other  documents  required to be filed under Sections  13(a),  13(c), 14 and
15(d) of the Exchange Act since  December 31, 2002 and prior to the date of this
Agreement. The Company meets the "Registrant Requirement" for eligibility to use
Form S-3 under the  Securities  Act in order to register  the  Company's  Common
Stock for resales.



                                      -4-


            (c) SEC Documents.  The Company has not provided to the Investor any
information  which according to applicable law, rule or regulation,  should have
been  disclosed  publicly  prior to the date hereof by the Company but which has
not been so disclosed. As of their respective dates, the SEC Documents complied,
and all  similar  documents  filed with the SEC prior to the  Closing  Date will
comply,  in all material respects with the requirements of the Securities Act or
the  Exchange  Act,  as the case may be,  and rules and  regulations  of the SEC
promulgated  thereunder  and other  federal,  state and  local  laws,  rules and
regulations  applicable  to such SEC  Documents,  and none of the SEC  Documents
contained, nor will any similar document filed with the SEC prior to the Closing
Date  contain,  any untrue  statement  of a material  fact or omitted to state a
material  fact  required to be stated  therein or necessary in order to make the
statements  therein,  in light of the circumstances  under which they were made,
not  misleading.  The financial  statements  of the Company  included in the SEC
Documents,  as of the dates thereof,  complied,  and all similar documents filed
with the SEC prior to the Closing Date will  comply,  as to form in all material
respects with  applicable  accounting  requirements  and the published rules and
regulations of the SEC and other  applicable  rules and regulations with respect
thereto.  Such financial  statements  were prepared in accordance with generally
accepted accounting  principles applied on a consistent basis during the periods
involved (except (i) as may be otherwise indicated in such financial  statements
or the notes thereto or (ii) in the case of unaudited interim statements, to the
extent they may not include footnotes or may be condensed or summary  statements
as  permitted  by Form  10-Q of the  SEC) and  fairly  present  in all  material
respects the financial position of the Company and its consolidated subsidiaries
as of the dates  thereof and the  consolidated  results of  operations  and cash
flows for the periods then ended (subject,  in the case of unaudited statements,
to normal year-end audit adjustments).

            (d)  Warrants.  The Company  agrees to issue to the  Investor at the
Closing,  transferable  divisible  warrants (the  "Warrants")  to purchase up to
800,000  shares of Common Stock.  Such Warrants shall bear an exercise price per
share of Common  Stock as set  forth in the  Warrants  and shall be  exercisable
immediately  upon issuance,  and for a period of three (3) years  following such
issuance.  Subject to the terms and conditions of the Warrants,  the Company, at
its option,  may, upon written  notice to the  Investor,  call up to one hundred
percent (100%) of the Warrants if the Common Stock trades at a price equal to or
greater than $3.00 per share for five (5) consecutive  trading days prior to the
date the Company calls the Warrants.

            (e) Reimbursement.  If (i) the Investor, other than by reason of its
gross negligence or willful misconduct,  becomes involved in any capacity in any
action,  proceeding or investigation  brought by any stockholder of the Company,
in  connection  with or as a  result  of the  consummation  of the  transactions
contemplated by this Purchase  Agreement,  or if such Investor  impleaded in any
such action,  proceeding or investigation  by any Person,  or (ii) the Investor,
other than by reason of its gross negligence or willful  misconduct or by reason
of its trading of the Common Stock in a manner that is illegal under the federal
securities  laws or other  actions,  becomes  involved  in any  capacity  in any
action,  proceeding  or  investigation  brought  by the  Commission  against  or
involving the Company or in connection  with or as a result of the  consummation
of the transactions  contemplated by this Purchase Agreement, or if the Investor
is impleaded in any such action, proceeding or investigation by any Person, then
in any such case,  the Company will  reimburse  the Investor for its  reasonable
legal  and  other  expenses   (including  the  cost  of  any  investigation  and
preparation) incurred in connection therewith, as such expenses



                                      -5-


are incurred.  In addition,  other than with respect to any such matter in which
the Investor is a named party, the Company will pay the Investor the charges, as
reasonably determined by the Investor, for the time of any officers or employees
of the Investor  devoted to  appearing  and  preparing  to appear as  witnesses,
assisting in preparation for hearings,  trials or pretrial matters, or otherwise
with respect to inquiries,  hearing,  trials, and other proceedings  relating to
the subject  matter of this  Agreement.  The  reimbursement  obligations  of the
Company under this  paragraph  shall be in addition to any  liability  which the
Company may otherwise  have,  shall extend upon the same terms and conditions to
any  Affiliates  of the  Investors  who  are  actually  named  in  such  action,
proceeding or  investigation,  and partners,  directors,  agents,  employees and
controlling  persons (if any), as the case may be, of the Investors and any such
Affiliate, and shall be binding upon and inure to the benefit of any successors,
assigns,  heirs and personal  representatives of the Company,  the Investors and
any such Affiliate and any such Person. The Company also agrees that neither the
Investor  nor any such  Affiliate,  partners,  directors,  agents,  employees or
controlling  persons  shall  have any  liability  to the  Company  or any person
asserting  claims on behalf of or in right of the Company in connection  with or
as a  result  of the  consummation  of the  transactions  contemplated  by  this
Purchase  Agreement  except to the  extent  that any  losses,  claims,  damages,
liabilities or expenses incurred by the Company result from the gross negligence
or willful misconduct of the Investor or any such Affiliate. The Company further
agrees  to  reimburse  the  Investor  for its  reasonable  attorney's  and other
professional  fees in  connection  with the  negotiation  and  execution of this
Purchase Agreement.

         5.  DELIVERY OF SHARES.  (a)  Promptly  following  the  delivery by the
Investor of the Total Purchase Price for the Shares in accordance with Section 1
hereof, the Company will irrevocably instruct its transfer agent to issue to the
Investor legended certificates representing the Shares.

            (b) Within five (5)  business  days (such third  business  day,  the
"Delivery  Date") after the business day on which the Company has received  both
the notice of sale (by  facsimile or other  delivery)  and the  original  Common
Stock  certificate (and if the same are not delivered to the Company on the same
date,  the date of delivery of the second of such items),  the Company (i) shall
deliver,  and shall cause legal counsel  selected by the Company to deliver,  to
its transfer  agent (with copies to Investor)  an  appropriate  instruction  and
opinion of such counsel, for the delivery of unlegended Shares issuable upon the
sale of the  Shares  pursuant  to the  registration  statement  for the  Shares;
provided that such registration  statement at the time of sale has been declared
effective by the Commission and is current (the "Unlegended  Shares");  and (ii)
transmit the certificates  representing the Unlegended Shares (together,  unless
otherwise  instructed  by the  Investor,  with  Common  Stock not sold),  to the
Investor at the address  specified in a notice of sale (which address may be the
Investor's  address  for  notices  as  contemplated  by  Section  6 hereof  or a
different address) via express courier, by electronic transfer or otherwise.

            (c) In lieu of delivering  physical  certificates  representing  the
Unlegended  Shares,  if the Company's  transfer  agent is  participating  in the
Depository  Trust Company ("DTC") Fast Automated  Securities  Transfer  program,
upon request of the Investor and its compliance with the provisions contained in
this paragraph,  so long as the  certificates  therefor do not bear a legend and
the  Investor  thereof  is not  obligated  to return  such  certificate  for the
placement of a legend  thereon,  the Company shall use its best efforts to cause
its transfer agent to



                                      -6-


electronically  transmit  the  Unlegended  Shares by  crediting  the  account of
Investor's Prime Broker with DTC through its Deposit Withdrawal Agent Commission
system.

         6. NOTICES.  Any notice required or permitted  hereunder shall be given
in writing (unless otherwise  specified herein) and shall be deemed  effectively
given upon  personal  delivery or seven (7) business  days after  deposit in the
United  States  Postal  Service,  by (a) advance copy by fax, and (b) mailing by
express  courier or registered or certified  mail with postage and fees prepaid,
addressed  to each of the other  parties  thereunto  entitled  at the  following
addresses,  or at such  other  addresses  as a party may  designate  by ten days
advance written notice to each of the other parties hereto.

            Company:          Xybernaut Corporation
                              12701 Fair Lakes Circle, Suite 550
                              Fairfax, Virginia  22033
                              ATTN:  Thomas D. Davis, Chief Financial Officer
                              Telephone No.:  (703) 631-6925
                              Facsimile No.:  (703) 631-3903

            with a copy to:   Jenkens & Gilchrist Parker Chapin LLP
                              The Chrysler Building
                              405 Lexington Avenue
                              New York, New York  10174
                              ATTN:  Martin Eric Weisberg, Esq.
                              Telephone No.:  (212) 704-6000
                              Facsimile No.:  (212) 704-6288

            Investor:         Essex Trading Ltd.
                              Fitzroy Mews 5, Suite No. 7
                              London, England
                              Facsimile No.: ______________


         7. SEVERABILITY.  If a court of competent jurisdiction  determines that
any provision of this Purchase  Agreement is invalid,  unenforceable  or illegal
for any  reason,  such  determination  shall not affect or impair the  validity,
legality and enforceability of the other provisions of this Purchase  Agreement.
If any such  invalidity,  unenforceability  or illegality of a provision of this
Purchase  Agreement becomes known or apparent to any of the parties hereto,  the
parties  shall  negotiate  promptly  and in good  faith  in an  attempt  to make
appropriate  changes and  adjustments  to such provision  specifically  and this
Purchase Agreement generally to achieve as closely as possible,  consistent with
applicable  law, the intent and spirit of such provision  specifically  and this
Purchase Agreement generally.

         8. EXECUTION IN COUNTERPARTS.  This Purchase  Agreement may be executed
in  counterparts,  each of which shall be deemed an  original,  but all of which
together shall constitute the same Purchase Agreement.



                                      -7-


         9. CONSENT  TO  JURISDICTION.  Each of the Company and the Investor (i)
hereby  irrevocably  submits to the  jurisdiction  of the United States District
Court  sitting in the Southern  District of New York and the courts of the State
of New York located in New York county for the  purposes of any suit,  action or
proceeding  arising  out of or relating to this  Agreement  or the  transactions
contemplated hereby and (ii) hereby waives, and agrees not to assert in any such
suit, action or proceeding,  any claim that it is not personally  subject to the
jurisdiction of such court, that the suit, action or proceeding is brought in an
inconvenient  forum or that the  venue of the  suit,  action  or  proceeding  is
improper.  Each of the Company and the Investor consents to process being served
in any such suit,  action or  proceeding by mailing a copy thereof to such party
at the address in effect for notices to it under this  Agreement and agrees that
such service shall constitute good and sufficient  service of process and notice
thereof.  Nothing  in this  Section  9 shall  affect or limit any right to serve
process in any other manner permitted by law.

         10.  GOVERNING  LAW. This Purchase  Agreement  shall be governed by and
interpreted in accordance  with the laws of the State of New York without giving
effect to choice of law provisions.


                             [SIGNATURES CONTINUED]






                                      -8-




         IN WITNESS WHEREOF,  the parties have executed this Purchase  Agreement
as of the date first written above.

                                      XYBERNAUT CORPORATION


                                      By:
                                          ------------------------------------
                                             Name:
                                             Title:



                                      ESSEX TRADING LTD.


                                      By:
                                          ------------------------------------
                                             Name:
                                             Title:








                                      -9-