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                                                                    EXHIBIT 10.1

                                                                  EXECUTION COPY



                  COMMON STOCK AND WARRANT PURCHASE AGREEMENT



                         Dated as of February 1, 2001



                                by and between



                         FIBERNET TELECOM GROUP, INC.



                                      and



                          THE PURCHASERS NAMED HEREIN


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                        COMMON STOCK PURCHASE AGREEMENT



     This COMMON STOCK AND WARRANT PURCHASE AGREEMENT (this "Agreement") is
dated as of February 1, 2001 by and among FiberNet Telecom Group, Inc., a
Delaware corporation (the "Company"), and the purchasers identified on Exhibit A
attached hereto (individually, a "Purchaser" and collectively, the
"Purchasers").

     The parties hereto agree as follows:

                                   ARTICLE I

                                  Definitions

          Section 1.1    Definitions.

          (a)  "Business Day" shall mean any day other than a Saturday, Sunday
or day on which banks are permitted to close in the State of Delaware.

          (b)  "Commission" shall have the meaning assigned to such term in
Section 2.3 hereof.

          (c)  "Commission Documents" shall have the meaning assigned to such
term in Section 3.1(d) hereof.

          (d)  "Commission Filings" means the Company's Form 10-KSB for the
fiscal year ended December 31, 1999, its Form 10-QSB for the fiscal quarter
ended March 31, 2000, its Form 10-QSB for the fiscal quarter ended June 30,
2000, its Form 10QSB for the fiscal quarter ended September 30, 2000, its Form
8-K filed on April 14, 2000, its Form 8-K filed on June 8, 2000, its Form 8-K
filed on July 11, 2000, its Form 8-K dated August 4, 2000, its Form 8-K filed on
August 15, 2000, its Registration Statement on Form S-3 (No. 333-43788), and all
other filings made by the Company after the date hereof pursuant to the
Securities Exchange Act of 1934, as amended (the "Exchange Act").

          (e)  "Material Adverse Effect" shall mean any effect on the business,
results of operations, assets or financial condition of the Company that is
material and adverse to the Company and its subsidiaries, taken as a whole
and/or any condition, circumstance, or situation that would prohibit the Company
from entering into and performing any of its obligations under this Agreement in
any material respect.

          (f)  "Prospectus" as used in this Agreement means the prospectus in
the form included in the Registration Statement, as supplemented from time to
time pursuant to Rule 424(b) of the Securities Act of 1933, as amended (the
"Securities Act").
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          (g)  "Registration Statement" shall mean the registration statement on
Form S-3, Commission File Number 333-43788, under the Securities Act, filed with
the Securities and Exchange Commission, and subsequently declared effective by
the Securities and Exchange Commission, for the registration of the Shares, as
such Registration Statement may be amended from time to time.

          (h)  "Shares" shall mean the Warrants and shares of Common Stock of
the Company that are sold under the terms of this Agreement.

                                  ARTICLE II

                 Purchase and Sale of Common Stock and Warrant

          Section 2.1    Authorization. The Company has duly authorized the sale
and issuance, pursuant to the terms of this Agreement, of (a) 6,440,000 shares
of its common stock, $0.001 par value per share (the "Common Stock") and (b)
warrants to purchase 1,288,000 shares of Common Stock (the "Warrants").

          Section 2.2    Purchase and Sale of Stock. Upon execution of this
Agreement, the Purchasers shall deliver the Purchase Price (as defined herein)
to the escrow agent pursuant to the Escrow Agreement attached hereto as Exhibit
B. Subject to the terms and conditions of this Agreement, at the Closing (as
defined in Section 2.4) the Company shall issue and sell to the Purchasers and
the Purchasers shall purchase from the Company in the aggregate 6,440,000 shares
of Common Stock at a purchase price of $4.375 per share, for an aggregate
purchase price of Twenty Eight Million One Hundred and Seventy Five Thousand
($28,175,000) (the "Purchase Price"), which amount shall include the Warrants.

          Section 2.3    Registration Statement and Prospectus. The Company has
prepared and filed with the Securities and Exchange Commission (the
"Commission") in accordance with the provisions of the Securities Act, the
Registration Statement, including a prospectus subject to completion relating to
the Shares.

          Section 2.4    Purchase Price, Closing and Settlement. In
consideration of and in express reliance upon the representations, warranties,
covenants, terms and conditions of this Agreement, the Company agrees to issue
and sell to the Purchasers and the Purchasers, agree to purchase from the
Company, the Warrants and that number of the shares of the Company's Common
Stock as set forth on Exhibit A to this Agreement. The purchase and sale of the
Shares, and release of the Purchase Price from escrow, (the "Closing") shall
take place at the offices of the Company on (i) a date not later than February
9, 2001 or (ii) such other place or date as the Purchasers and the Company may
agree upon (the "Closing Date"). Each party shall deliver all documents,
instruments and writings required to be delivered by such party pursuant to this
Agreement at or prior to the Closing. On the Closing Date, the Company shall
deliver the Shares purchased by the Purchasers to the Purchasers or their
designee, as indicated in writing by the Purchasers, against payment therefor to
the Company's designated account by wire transfer of immediately available
funds. In the event the Escrow Agreement terminates and is no longer

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of any force or effect prior to Closing, then this Agreement shall terminate and
the parties hereto shall have no further obligations under this Agreement.


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                                  ARTICLE III

                        Representations and Warranties

          Section 3.1    Representations and Warranties of the Company. The
Company hereby makes the following representations and warranties to the
Purchasers:

          (a)  Organization, Good Standing and Power. The Company is a
corporation duly incorporated, validly existing and in good standing under the
laws of Delaware and has the requisite corporate power to own, lease and operate
its properties and assets and to conduct its business as it is now being
conducted. As of the date hereof, the Company does not have any subsidiaries (as
defined in Section 3.1(g)) except as set forth in the Registration Statement and
in the Company's most recent Form 10-KSB, including the accompanying financial
statements (the "Form 10-K"), or in the Company's most recent Form 10-QSB (the
"Form 10-Q"), or on Schedule 3.1(e) attached hereto. The Company and each such
subsidiary is duly qualified to do business as a foreign corporation and is in
good standing in every jurisdiction in which the nature of the business
conducted or property owned by it makes such qualification necessary except for
any jurisdiction in which the failure to be so qualified will not have a
Material Adverse Effect.

          (b)  Authorization; Enforcement. The Company has the requisite
corporate power and authority to enter into and perform this Agreement and to
issue and sell the Shares in accordance with the terms hereof. The execution,
delivery and performance of this Agreement by the Company and the consummation
by it of the transactions contemplated hereby have been duly and validly
authorized by all necessary corporate action, and no further consent or
authorization of the Company or its Board of Directors or stockholders is
required. This Agreement has been duly executed and delivered by the Company.
This Agreement constitutes, or when executed and delivered shall constitute, a
valid and binding obligation of the Company enforceable against the Company in
accordance with its terms, except as such enforceability may be limited by
applicable bankruptcy, insolvency, reorganization, moratorium, liquidation,
conservatorship, receivership or similar laws relating to, or affecting
generally the enforcement of, creditor's rights and remedies or by other
equitable principles of general application.

          (c)  Issuance of Shares. The Shares have been duly authorized by all
necessary corporate action and, when paid for or issued in accordance with the
terms hereof, the Common Stock shall be validly issued and outstanding, fully
paid and non-assessable, and upon payment of the exercise price in accordance
with the terms of the Warrant Agreement, the form of which is attached hereto as
Exhibit C, the shares of Common Stock issuable upon exercise of the Warrants
shall be validly issued and outstanding, fully paid and non-assessable.

          (d)  Commission Documents, Financial Statements. The Common Stock of
the Company is registered pursuant to Section 12(b) or 12(g) of the Exchange
Act, and, except as disclosed in the Registration Statement, or the Commission
Documents or the Commission Filings, as of the date hereof, the Company has
timely filed all reports, schedules, forms, statements and other documents
required to be filed by it with the Commission pursuant to the

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reporting requirements of the Exchange Act, including material filed pursuant to
Section 13(a) or 15(d) of the Exchange Act (all of the foregoing including
filings incorporated by reference therein being referred to herein as the
"Commission Documents"). The Company has made available to the Purchasers true
and complete copies of the Commission Documents filed with the Commission since
December 31, 1999 and prior to the Closing Date. The Company has not provided to
the Purchasers any information which, according to applicable law, rule or
regulation, should have been disclosed publicly by the Company but which has not
been so disclosed, other than with respect to the transactions contemplated by
this Agreement. The Form 10-KSB for the year ended December 31, 1999 complied in
all material respects with the requirements of the Exchange Act and the rules
and regulations of the Commission promulgated thereunder and other federal,
state and local laws, rules and regulations applicable to such document, and, as
of its date, such Form 10-KSB did not contain any untrue statement of a material
fact or omit 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 Commission Documents complied as to form in all material
respects with applicable accounting requirements and the published rules and
regulations of the Commission or other applicable rules and regulations with
respect thereto. Such financial statements have been prepared in accordance with
generally accepted accounting principles ("GAAP") 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), and fairly present in all material respects
the financial position of the Company and its subsidiaries as of the dates
thereof and the results of operations and cash flows for the periods then ended
(subject, in the case of unaudited statements, to normal year-end audit
adjustments).

          (e)  Subsidiaries. The Commission Documents or Schedule 3.1(e) set
forth each subsidiary of the Company as of the date hereof, showing the
jurisdiction of its incorporation or organization. For the purposes of this
Agreement, "subsidiary" shall mean any corporation or other entity of which at
least a majority of the securities or other ownership interest having ordinary
voting power (absolutely or contingently) for the election of directors or other
persons performing similar functions are at the time owned directly or
indirectly by the Company and/or any of its other subsidiaries. Except as set
forth in the Commission Documents or the Commission Filings, none of such
subsidiaries is a "significant subsidiary" as defined in Regulation S-X.

          (f)  Certain Fees. Other than the fees of H.C. Wainwright & Co., Inc.
and Kaufman Bros., L.P., for which the Company shall be solely responsible, no
brokers, finders or financial advisory fees or commissions will be payable by
the Company or any subsidiary with respect to the transactions contemplated by
this Agreement.

          (g)  Securities Act of 1933. The Company has complied in all material
respects with all applicable federal and state securities laws in connection
with the offer, issuance and sale of the Shares hereunder.

               (i)       Each Prospectus included as part of the Registration
Statement as originally filed or as part of any amendment or supplement thereto,
or filed pursuant to Rule 424

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under the Securities Act, complied when so filed in all material respects with
the provisions of the Securities Act. The Commission has not issued any order
preventing or suspending the use of any Prospectus.

               (ii)      The Company meets the requirements for the use of Form
S-3 under the Securities Act. The Registration Statement in the form in which it
became effective and also in such form as it may be when any post-effective
amendment thereto became effective and the Prospectus and any supplement or
amendment thereto when filed with the Commission under Rule 424(b) under the
Securities Act, complied in all material respects with the provisions of the
Securities Act and did not at any such times contain an untrue statement of a
material fact or omit to state a material fact required to be stated therein or
necessary to make the statements therein (in the case of the Prospectus, in the
light of the circumstances under which they were made) not misleading, except
that this representation and warranty does not apply to statements in or
omissions from the Registration Statement or the Prospectus made in reliance
upon and in conformity with information relating to the Purchasers furnished to
the Company in writing by or on behalf of the Purchasers expressly for use
therein.

               (iii)     The Company has not distributed and, prior to the
completion of the sale of the Shares to the Purchasers, will not distribute any
offering material in connection with the offer and sale of the Shares other than
the Registration Statement, the Prospectus or other materials, if any, permitted
by the Securities Act.

          (h)  Use of Proceeds. The proceeds from the sale of the Shares will be
used by the Company and its subsidiaries for the purposes set forth in the
Prospectus under "Use of Proceeds."

          (i)  Registration Statement. The sale and issuance by the Company of
the Shares have been validly registered pursuant to the Registration Statement
and such shares of Common Stock will be issued without a restrictive legend.

          Section 3.2    Representations, Warranties and Covenants of the
Purchasers. Each Purchaser, individually on behalf of itself, hereby makes the
following representations, warranties and covenants to the Company:

          (a)  Organization and Standing of the Purchaser. The Purchaser is an
entity duly organized, validly existing and in good standing under the laws of
the jurisdiction identified on Exhibit A .

          (b)  Authorization and Power. The Purchaser has the requisite power
and authority to enter into and perform this Agreement and to purchase the
Shares in accordance with the terms hereof. The execution, delivery and
performance of this Agreement by the Purchaser and the consummation by it of the
transactions contemplated hereby have been duly authorized by all necessary
action, and no further consent or authorization of the Purchaser, its Board of
Directors or stockholders is required. This Agreement constitutes, or when
executed and delivered shall constitute, a valid and binding obligation of the
Purchaser enforceable against the Purchaser in accordance with its terms, except
as such enforceability may be limited by applicable bankruptcy, insolvency,
reorganization, moratorium, liquidation, conservatorship,

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receivership, or similar laws relating to, or affecting generally the
enforcement of creditor's rights and remedies or by other equitable principles
of general application.

          (c)  No Conflicts. The execution, delivery and performance of this
Agreement and the consummation by the Purchaser of the transactions contemplated
hereby and thereby or relating hereto do not and will not (i) result in a
violation of such Purchaser's charter documents or bylaws or (ii) conflict with,
or constitute a default (or an event which with notice or lapse of time or both
would become a default) under, or give to others any rights of termination,
amendment, acceleration or cancellation of any material agreement, mortgage,
deed of trust, indenture, note, bond, license, lease agreement, instrument or
obligation to which the Purchaser is a party, (iii) create or impose or lien,
charge or encumbrance on any property of the Purchaser under any agreement or
any commitment to which the Purchaser is party or by which the Purchaser is on
or by which any of its respective properties or assets are bound or (iv) result
in a violation of any law, rule or regulation, or any order, judgment or decree
of any court or governmental agency applicable to the Purchaser or its
properties, except for such conflicts, defaults and violations as would not,
individually or in the aggregate, prohibit or otherwise interfere with the
ability of the Purchaser to enter into and perform its obligations under this
Agreement in any material respect. The Purchaser is not required to obtain any
consent, authorization or order of, or make any filing or registration with, any
court or governmental agency in order for it to execute, deliver or perform any
of its obligations under this Agreement or to purchase the Shares in accordance
with the terms hereof.

          (d)  Information. The Purchaser and its advisors, if any, have been
furnished with all materials relating to the business, finances and operations
of the Company and materials relating to the offer and sale of the Shares which
have been requested by the Purchaser to the extent such information is either
publicly available or not of a material nature. The Purchaser and its advisors,
if any, have been afforded the opportunity to ask questions of the Company. The
Purchaser has sought such accounting, legal and tax advice as it has considered
necessary to make an informed investment decision with respect to its
acquisition of the Shares. Purchaser understands that it (and not the Company)
shall be responsible for its own tax liabilities that may arise as a result of
this investment or the transactions contemplated by this Agreement.

          (e)  Investment Intent. The Purchaser is purchasing the Shares for its
own account for investment and not with a view toward the resale or distribution
thereof to others, and has no intent of undertaking special selling activities
with respect to the Company's Common Stock.

                                  ARTICLE IV

                                   Covenants

     The parties covenant with each other as follows, which covenants are for
the benefit of the party indicated and its or their permitted assignees.

          Section 4.1    Securities. The Company shall notify the Commission and
NASDAQ, if applicable, in accordance with their rules and regulations, of the
transactions contemplated by this Agreement, and shall take all other necessary
action and proceedings as

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may be required and permitted by applicable law, rule and regulation, for the
legal and valid issuance of the Shares to the Purchasers or subsequent holders.

          Section 4.2    Registration and Listing. The Company will take all
action necessary to cause its Common Stock to continue to be registered under
Sections 12(b) or 12(g) of the Exchange Act, will comply in all respects with
its reporting and filing obligations under the Exchange Act, and will not take
any action or file any document (whether or not permitted by the Securities Act
or the rules promulgated thereunder) to terminate or suspend such registration
or to terminate or suspend its reporting and filing obligations under the
Exchange Act or Securities Act, except as permitted herein. The Company will
take all action necessary to continue the listing or trading of its Common Stock
and the listing of the Shares purchased by the Purchasers hereunder on the
NASDAQ or any relevant market or system, if applicable, and will comply in all
respects with the Company's reporting, filing and other obligations under the
bylaws or rules of the NASD or any relevant market or system.

          Section 4.3    Compliance with Laws. The Company shall comply, and
cause each subsidiary to comply, with all applicable laws, rules, regulations
and orders, noncompliance with which could reasonably be expected to have a
Material Adverse Effect.

          Section 4.4    Keeping of Records and Books of Account. The Company
shall keep and cause each subsidiary to keep adequate records and books of
account, in which complete entries will be made in accordance with GAAP
consistently applied, reflecting all financial transactions of the Company and
its subsidiaries, and in which, for each fiscal year, all proper reserves for
depreciation, depletion, obsolescence, amortization, taxes, bad debts and other
purposes in connection with its business shall be made.

          Section 4.5    Non-public Information. Neither the Company nor any of
its officers or agents shall disclose any material non-public information about
the Company to the Purchasers and neither the Purchasers nor any of its
affiliates, officers or agents will solicit any material non-public information
from the Company.

          Section 4.6    Prospectus Delivery. Upon Closing, the Company will
deliver to the Purchasers, without charge, in such quantities as reasonably
requested by the Purchasers, copies of each form of Prospectus (and any
amendment or supplement thereto). As soon after the Closing as possible and
thereafter from time to time for such period as in the opinion of counsel for
the Purchasers a prospectus is required by the Securities Act to be delivered in
connection with sales by the Purchasers, the Company will expeditiously deliver
to the Purchasers, without charge, as many copies of the Prospectus (and of any
amendment or supplement thereto) as the Purchasers may reasonably request. The
Company consents to the use of the Prospectus (and of any amendment or
supplement thereto) in accordance with the provisions of the Securities Act and
with the securities or Blue Sky laws of the jurisdictions in which the Shares
may be sold by the Purchasers, in connection with the offering and sale of the
Shares and for such period of time thereafter as the Prospectus is required by
the Securities Act to be delivered in connection with sales of the Shares. If
during such period of time any event shall occur that in the judgment of the
Company or in the opinion of counsel for the Purchasers is required to be set
forth in the Prospectus (as then amended or supplemented) or should be set

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forth therein in order to make the statements therein, in the light of the
circumstances under which they were made, not misleading, or if it is necessary
to supplement or amend the Prospectus to comply with the Securities Act or any
other law, the Company will forthwith prepare and file with the Commission an
appropriate supplement or amendment thereto, and will expeditiously furnish to
the Purchasers a reasonable number of copies thereof.

          Section 4.7    Effective Registration Statement. If, at the time this
Agreement is executed and delivered, it is necessary for the Registration
Statement or a post-effective amendment thereto to be declared effective before
the offering of the Shares may commence, the Company will endeavor to cause the
Registration Statement or such post-effective amendment to become effective as
soon as reasonably practicable and will advise the Purchasers promptly and, if
requested by the Purchasers, will confirm such advice in writing, when the
Company receives notice that the Registration Statement or such post-effective
amendment has become effective.

                                   ARTICLE V

                             Conditions to Closing

          Section 5.1    Conditions Precedent to the Obligation of the Company
to Close this Agreement and to Sell the Shares. The obligation hereunder of the
Company to issue and sell the Shares to the Purchasers is subject to the
satisfaction or waiver of each of the conditions set forth below. These
conditions are for the Company's sole benefit and may be waived by the Company
at any time in its sole discretion.

          (a)  Accuracy of the Purchaser's Representations and Warranties. The
Purchaser shall deliver a certificate to the effect that the representations and
warranties of each of the Purchasers shall be true and correct in all material
respects as of the Closing Date with the same effect as though such
representation and warranty had been made on and as of that date.

          (b)  Effective Registration Statement. The Registration Statement
registering the offer and sale of the Shares shall have been declared effective
by the Commission.

          (c)  Performance by the Purchasers. The Purchasers shall have
performed, satisfied and complied in all material respects with all covenants,
agreements and conditions required by this Agreement to be performed, satisfied
or complied with by the Purchasers.

          (d)  No Injunction. No statute, regulation, executive order, decree,
ruling or injunction shall have been enacted, entered, promulgated or endorsed
by any court or governmental authority of competent jurisdiction which prohibits
the consummation of any of the transactions contemplated by this Agreement.

          (e)  No Suspension, Etc. Trading in the Company's Common Stock shall
not be suspended by the Commission or the NASD (except for any suspension of
trading of limited duration agreed to by the Company, which suspension shall be
terminated prior to Closing), and, at any time prior to the Closing, trading in
securities generally as reported on NASDAQ shall not have been suspended or
limited, or minimum prices shall not have been established on securities

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whose trades are reported by American Stock Exchange, or on the New York Stock
     Exchange, nor shall a banking moratorium have been declared either by the
     United States or New York State authorities, nor shall there have occurred
     any material outbreak or escalation of hostilities or other national or
     international calamity or crisis of such magnitude in its effect on, or any
     material adverse change in any financial market which, in each case, in the
     judgment of the Company, makes it impracticable or inadvisable to issue the
     Shares.

          (f)  No Proceedings or Litigation. No action, suit or proceeding
before any arbitrator or any governmental authority shall have been commenced,
and no investigation by any governmental authority shall have been threatened,
against the Company or any subsidiary, or any of the officers, directors or
affiliates of the Company or any subsidiary seeking to restrain, prevent or
change the transactions contemplated by this Agreement, or seeking damages in
connection with such transactions.

          (g)  Warrant Agreement. The Purchasers shall have entered into the
Warrant Agreement.

          (h)  Escrow Agreement. The Escrow Agreement shall not have been
terminated and shall be in full force and effect.

          Section 5.2    Conditions Precedent to the Obligation of the
Purchasers to Close this Agreement. The obligation hereunder of the Purchasers
to purchase the Shares set forth opposite the Purchasers' name on Exhibit A is
subject to the satisfaction or waiver, at or before the Closing, of each of the
conditions set forth below. These conditions are for the Purchasers' sole
benefit and may be waived by the Purchasers at any time in their sole
discretion.

          (a)  Performance by the Company. The Company shall have performed,
satisfied and complied in all material respects with all covenants, agreements
and conditions required by this Agreement to be performed, satisfied or complied
with by the Company at or prior to the Closing.

          (b)  No Suspension, Etc. Trading in the Company's Common Stock shall
not be suspended by the Commission or the NASD (except for any suspension of
trading of limited duration agreed to by the Company, which suspension shall be
terminated prior to Closing), and, at any time prior to the Closing, trading in
securities generally as reported on NASDAQ shall not have been suspended or
limited, or minimum prices shall not have been established on securities whose
trades are reported by the American Stock Exchange, or on the New York Stock
Exchange, nor shall a banking moratorium have been declared either by the United
States or New York State authorities, nor shall there have occurred any material
outbreak or escalation of hostilities or other national or international
calamity or crisis of such magnitude in its effect on, or any material adverse
change in any financial market which, in each case, in the judgment of the
Purchasers, makes it impracticable or inadvisable to purchase the Shares.

          (c)  No Injunction. No statute, rule, regulation, executive order,
decree, ruling or injunction shall have been enacted, entered, promulgated or
endorsed by any court or governmental authority of competent jurisdiction which
prohibits the consummation of any of the transactions contemplated by this
Agreement.

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          (d)  No Proceedings or Litigation. No action, suit or proceeding
before any arbitrator or any governmental authority shall have been commenced,
and no investigation by any governmental authority shall have been threatened,
against the Company or any subsidiary, or any of the officers, directors or
affiliates of the Company or any subsidiary seeking to restrain, prevent or
change the transactions contemplated by this Agreement, or seeking damages in
connection with such transactions.

          (e)  Opinion of Counsel, Etc. At the Closing, the Purchasers shall
have received an opinion of counsel to the Company, dated the date of Closing,
in the form of Exhibit D hereto, and such other certificates and documents as
the Purchasers or their counsel shall reasonably require incident to the
Closing.

          (f)  Warrant Agreement. The Company shall have entered into the
Warrant Agreement.

          (g)  Escrow Agreement. The Escrow Agreement shall not have been
terminated and shall be in full force and effect.

          (h)  Prospectus Supplement. The Company shall have filed a Prospectus
Supplement registering the Shares pursuant to the Registration Statement on Form
S-3 (Registration Number 333-43788).

          (i)  Credit Agreement Amendment. The Company shall have amended its
Credit Agreement dated April 11, 2000 (the "Credit Agreement"), to the extent
necessary to allow for the purchase and sale of the Shares contemplated by this
Agreement without invoking any mandatory prepayment or other provisions of the
Credit Agreement which may restrict or in anyway limit (i) the ability of the
Company to effectuate the purchase and sale of the Shares or (ii) the use of the
proceeds received by the Company upon the purchase and sale of the Shares.

          (j)  Bank Facility Increase The Company shall have received a written
commitment from the Lenders, as such term is defined in the Credit Agreement,
agreeing to increase the Company's credit facility from $75 million to an amount
not less than $100 million.

          (k)  Accuracy of the Company's Representations and Warranties. The
Company shall deliver a certificate, executed by an officer of the Company, to
the effect that the representations and warranties of the Company shall be true
and correct in all material respects as of the Closing Date with the same effect
as though such representations and warranties had been made on and as of that
date.

                                  ARTICLE VI

                                 Miscellaneous

          Section 6.1    Fees and Expenses. Each of the parties to this
Agreement shall be responsible for the payment of their own fees and expenses
incurred in connection with the preparation, negotiation and execution of this
Agreement and the transactions contemplated hereby whether or not the
transactions contemplated hereby are consummated.

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          Section 6.2    Specific Enforcement, Consent to Jurisdiction.

          (a)  The Company and the Purchasers acknowledge and agree that
irreparable damage would occur in the event that any of the provisions of this
Agreement were not performed in accordance with their specific terms or were
otherwise breached. It is accordingly agreed that the parties shall be entitled
to an injunction or injunctions to prevent or cure breaches of the provisions of
this Agreement and to enforce specifically the terms and provisions hereof or
thereof, this being in addition to any other remedy to which any of them may be
entitled by law or equity.

          (b)  Each of the Company and the Purchasers (i) hereby irrevocably
submits to the jurisdiction of the United States District Court and other courts
of the United States sitting in The State of New York for the purposes of any
suit, action or proceeding arising out of or relating to this Agreement 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 Purchasers consent 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 agree that such service shall constitute
good and sufficient service of process and notice thereof. Nothing in this
Section shall affect or limit any right to serve process in any other manner
permitted by law.

          Section 6.3    Entire Agreement; Amendment. This Agreement contains
the entire understanding of the parties with respect to the matters covered
hereby and, except as specifically set forth herein, neither the Company nor the
Purchasers make any representations, warranty, covenant or undertaking with
respect to such matters. No provision of this Agreement may be waived or amended
other than by a written instrument signed by the party against whom enforcement
of any such amendment or waiver is sought.

          Section 6.4    Notices. Any notice, demand, request, waiver or other
communication required or permitted to be given hereunder shall be in writing
and shall be effective if delivered to the Company in the manner set forth below
to the address or number set forth below and to the Purchasers in the manner set
forth below to the address or number set forth on Exhibit B, in each case (a)
upon hand delivery, by telex (with correct answer back received), telecopy or
facsimile (if delivered on a business day during normal business hours where
such notice is to be received), or the first business day following such
delivery (if delivered other than on a business day during normal business hours
where such notice is to be received) or (b) on the second business day following
the date of mailing by express courier service, fully prepaid, addressed to such
address, or upon actual receipt of such mailing, whichever shall first occur.
The addresses for such communications to the Company shall be:

                                      12
<PAGE>

                         FiberNet Telecom Group, Inc.
                         570 Lexington Avenue
                         New York, New York 10022
                         Tel. No.: (212) 405-6200
                         Fax No.:  (212) 421-8920
                         Attention:  Michael S. Liss,
                                     President and Chief Executive Officer

With copies to:          Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.
                         Chrysler Center
                         666 Third Avenue
                         New York, New York  10022
                         Tel. No.: (212) 935-3000
                         Fax No.: (212) 983-3115
                         Attention:  Gordon Caplan, Esq.

     Any party hereto may from time to time change its address for notices by
giving at least ten (10) days prior written notice of such changed address to
the other party hereto.

          Section 6.5    Waivers. No waiver by either party of any default with
respect to any provision, condition or requirement of this Agreement shall be
deemed to be a continuing waiver in the future or a waiver of any other
provisions, condition or requirement hereof, nor shall any delay or omission of
any party to exercise any right hereunder in any manner impair the exercise of
any such right accruing to it thereafter.

          Section 6.6    Headings. The article, section and subsection headings
in this Agreement are for convenience only and shall not constitute a part of
this Agreement for any other purpose and shall not be deemed to limit or affect
any of the provisions hereof.

          Section 6.7    Successors and Assigns. The Purchasers may not assign
this Agreement to any person without the prior written consent of the Company,
which consent will not be unreasonably withheld. This Agreement shall be binding
upon and inure to the benefit of the parties and their successors and assigns.
After Closing, the assignment by a party to this Agreement of any rights
hereunder shall not affect the obligations of such party under this Agreement.

          Section 6.8    Governing Law. This Agreement shall be governed by and
construed in accordance with the internal laws of the State of New York, without
giving effect to the choice of law provisions.

          Section 6.9    Survival. The representations and warranties of the
Company and each of the Purchasers contained in Article III and the covenants
contained in Article IV shall survive the execution and delivery hereof and the
Closing until the one (1) year anniversary of the date of the Closing.

                                      13
<PAGE>

          Section 6.10   Counterparts. This Agreement may be executed in any
number of counterparts, all of which taken together shall constitute one and the
same instrument and shall become effective when counterparts have been signed by
each party and delivered to the other parties hereto, it being understood that
all parties need not sign the same counterpart. In the event any signature is
delivered by facsimile transmission, the party using such means of delivery
shall cause four additional executed signature pages to be physically delivered
to the other parties within five days of the execution and delivery hereof.

          Section 6.11   Publicity. Prior to the Closing, neither the Company
nor any Purchaser shall issue any press release or otherwise make any public
statement or announcement with respect to this Agreement or the transactions
contemplated hereby or the existence of this Agreement. Promptly after the
Closing, the Company may issue a press release or otherwise make a public
statement or announcement with respect to this Agreement or the transactions
contemplated hereby or the existence of this Agreement, provided, however, that
in the event such press release contains the identity of any of the Purchasers
or quotes of any of the Purchasers, then prior to issuing any such press
release, making any such public statement or announcement, the Company shall
obtain the prior consent of such Purchaser identified or quoted, which consent
shall not be unreasonably withheld or delayed. Notwithstanding the foregoing, in
the event the Company is required by law, based upon an opinion of the Company's
counsel, to issue a press release or otherwise make a public statement or
announcement with respect to this Agreement prior to or after the Closing, the
Company shall consult with the Purchasers on the form and substance of such
press release or other disclosure.

          Section 6.12   Severability. The provisions of this Agreement are
severable and, in the event that any court of competent jurisdiction shall
determine that any one or more of the provisions or part of the provisions
contained in this Agreement shall, for any reason, be held to be invalid,
illegal or unenforceable in any respect, such invalidity, illegality or
unenforceability shall not affect any other provision or part of a provision of
this Agreement, and this Agreement shall be reformed and construed as if such
invalid or illegal or unenforceable provision, or part of such provision, had
never been contained herein, so that such provisions would be valid, legal and
enforceable to the maximum extent possible.

          Section 6.13   Further Assurances. From and after the date of this
Agreement, upon the request of the Purchasers or the Company, each of the
Company and the Purchasers shall execute and deliver such instrument, documents
and other writings as may be reasonably necessary or desirable to confirm and
carry out and to effectuate fully the intent and purposes of this Agreement.

           [THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK]

                                      14
<PAGE>

     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed by their respective authorized officers as of the date first above
written.

                                             FIBERNET TELECOM GROUP, INC.


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


                                             [________________________]


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


                                             [________________________]


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


                                      15
<PAGE>

                                   EXHIBIT A

            Number of Shares of Common Stock and Warrants Purchased
<PAGE>

                               EXHIBIT B TO THE
                  COMMON STOCK AND WARRANT PURCHASE AGREEMENT


ESCROW AGREEMENT
<PAGE>

                               EXHIBIT C TO THE
                  COMMON STOCK AND WARRANT PURCHASE AGREEMENT


FORM OF WARRANT AGREEMENT

                                       2
<PAGE>

                               EXHIBIT D TO THE

                  COMMON STOCK AND WARRANT PURCHASE AGREEMENT

MINTZ LEVIN OPINION

                                       3
<PAGE>

                             DISCLOSURE SCHEDULES
                   RELATING TO THE COMMON STOCK AND WARRANT
            PURCHASE AGREEMENT, DATED AS OF EBRUARY 1, 2001 BETWEEN
                       FIBERNET TELECOM GROUP, INC. AND
                         THE PURCHASERS NAMED THEREIN

     ALL SECTION AND SUBSECTION NUMBERS AND LETTERS RELATE AND COINCIDE TO SUCH
NUMBERS AND LETTERS AS SET FORTH  IN THE COMMON STOCK AND WARRANT PURCHASE
AGREEMENT (THE "AGREEMENT").  ANY CAPITALIZED TERMS USED HEREIN WITHOUT
DEFINITION SHALL HAVE THE MEANINGS ASCRIBED TO SUCH TERMS IN THE AGREEMENT.

     ALL REPRESENTATIONS AND WARRANTIES SET FORTH IN THE AGREEMENT ARE MODIFIED
IN THEIR ENTIRETY BY THESE DISCLOSURE SCHEDULES.  THE DISCLOSURES CONTAINED IN
THESE DISCLOSURE SCHEDULES SHALL BE READ IN THEIR ENTIRETY, AND ALL THE
DISCLOSURES SHALL BE READ TOGETHER.
<PAGE>

                              INDEX OF SCHEDULES

Schedule 3.1(e) - Subsidiaries
<PAGE>

                                Schedule 3.1(e)

                                 Subsidiaries
                                 ------------

------------------------------------------------------------------------------
 Subsidiaries of FiberNet          State of Incorporation   Ownership Interest
 Telecom Group, Inc.                  or Organization
------------------------------------------------------------------------------

FiberNet Operations, Inc.                 Delaware                 100%
------------------------------------------------------------------------------

FiberNet Telecom, Inc. (1)                Delaware                 100%
------------------------------------------------------------------------------

FiberNet Equal Access, L.L.C. (2)         New York                 100%
------------------------------------------------------------------------------

Local Fiber, L.L.C. (2)                   New York                 100%
------------------------------------------------------------------------------

Devnet, L.L.C. (3)                        Delaware                 100%
------------------------------------------------------------------------------

(1) FiberNet Operations, Inc. owns 100% of the capital stock.

(2) FiberNet Telecom, Inc. owns 100% of the membership interests.

(3) The FiberNet Telecom Group, Inc. owns 96.386% of the membership interests
and FiberNet Operations, Inc. owns 3.614% of the membership interests.