COMMON STOCK PURCHASE AGREEMENT

         THIS COMMON STOCK PURCHASE  AGREEMENT is dated as of September 29, 2000
(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 ARCHWAY HOLDINGS
LIMITED,  Gretton House,  P.O. Box 65, Duke Street,  Grand Turk,  Turks & Caicos
Islands, British West Indies. (the "Investor").

                               W I T N E S S E T H

         WHEREAS,  the Company wishes sell to the Investor,  and the Investor is
willing to buy from the Company,  subject to the terms and  conditions set forth
herein,  $3,000,000 (the "Total Purchase Price") 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 the Total  Purchase  Price  divided by a 24%  discount of the  Purchase
Price (as defined hereinafter) (the "Shares"), resulting in 717,703 Shares to be
issued  upon the  payment  of the  Purchase  Price.  Upon  receipt  of the Total
Purchase  Price,  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.
<PAGE>

                  (b) As used herein  "Purchase Price" shall mean the lowest bid
price of the Common Stock during the trading day  immediately  prior to the date
hereof.

                  (c) 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

                                       2
<PAGE>

the Company are bound, (iv) to the Company's knowledge, violate any statute, law
or regulation.

            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 Warrants and the
shares of Common Stock  issuable  upon  exercise of the 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;

                  (g) The Investor does not have a present intention to sell the
Shares, the Warrants or the Warrant Shares (collectively, 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;

                                       3
<PAGE>

                  (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
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 Shares,  the Warrants and the Warrant Shares to
the effect that the Shares,  the Warrants and the Warrant Shares,  respectively,
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
use its best  efforts  to  register  the Shares  and the  Warrant  Shares and to
include the Shares and the shares of Common Stock  issuable upon exercise of the
Warrants  set forth in Section 4(d) hereof,  in a  registration  statement to be
filed with the  Securities  and Exchange  Commission  on or before  November 15,
2000.

                  (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

                                       4
<PAGE>

Company  since  December  31,  1999 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, 1999 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
January 1, 1999 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.

                  (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
119,880  shares of Common Stock.  Such Warrants shall bear an exercise price per
share of Common Stock equal to $6.25 and shall be exercisable,  immediately upon
issuance,  and for a period of five (5) years  thereafter,  in the form  annexed
hereto as Exhibit  4(d).  The  Warrants  shall be callable by the Company if the
market price of the Shares  exceeds two hundred  percent  (200%) of the Purchase
Price for any ten (10) trading days during a fifteen (15) trading day period.

                                       5
<PAGE>

                  (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 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 Transaction  Documents 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.

         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

                                       6
<PAGE>

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 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:  John F. Moynahan, Chief Financial Officer
                          Telephone No.:  (703) 631-6925
                          Facsimile No.:  (703) 631-3903

     with a copy to:      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:     At the address set forth on the first page of this Agreement.

                                       7
<PAGE>

     with a copy to:      Krieger & Prager, LLP
                          39 Broadway, Suite 1440
                          New York, New York  10006
                          ATTN:  Samuel Krieger
                          Telephone No.:  (212) 363-2900
                          Facsimile No.:  (212) 363-2999

         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.

         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.


                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

                                       8
<PAGE>

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

                                      XYBERNAUT CORPORATION


                                      By: ______________________________________
                                          Name: Steven Newman
                                          Title:  Vice Chairman

                                      ARCHWAY HOLDINGS LIMITED


                                      By: ______________________________________
                                          Name: ________________________________
                                          Title: _______________________________



                                       9