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                                                                    EXHIBIT 10.1

                                                               EXECUTION VERSION

                                VOTING AGREEMENT

                  This VOTING AGREEMENT (this "Agreement"), is made and entered
into this 25th day of September 2003 by and among LI Acquisition Company, LLC, a
Maryland limited liability company ("Buyer"), FTI Consulting, Inc., a Maryland
corporation ("FTI"), Knowledge Universe, Inc., a Delaware corporation
("Knowledge Universe") and Nextera Enterprises Holdings, Inc., a Delaware
corporation ("Nextera Holdings", together with Knowledge Universe, collectively,
the "Stockholders").

                  WHEREAS, pursuant to the terms and subject to the conditions
of that certain Asset Purchase Agreement, dated as of September 25, 2003 (the
"Purchase Agreement"), by and among FTI, Buyer, Nextera Enterprises, Inc.
("Nextera"), Lexecon Inc. ("Lexecon"), CE Acquisition Corp. ("CE") and ERG
Acquisition Corp. ("ERG" and, together with Lexecon and CE, the "Sellers"),
Buyer shall purchase substantially all the assets of the Sellers (the
"Transaction");

                  WHEREAS, Nextera owns one hundred percent (100%) of the issued
and outstanding capital stock of Lexecon, and Lexecon owns one hundred percent
(100%) of the issued and outstanding capital stock of each of CE and ERG;

                  WHEREAS, the Stockholders are the holders of record or
beneficial owners (for all purposes in this Agreement, as such term is defined
in Rule 13d-3 of the Rules and Regulations promulgated by the Securities and
Exchange Commission pursuant to the Securities Exchange Act of 1934, as amended
(the "Exchange Act")) of 8,810,000 shares of the outstanding class A common
stock, par value $0.001 per share of Nextera (the "Class A Common Stock"),
3,844,200 shares of the outstanding class B common stock, par value $0.001 per
share of Nextera (the "Class B Common Stock," and together with the Class A
Common Stock, the "Common Stock"), and 40,375 shares of the outstanding series A
cumulative convertible preferred stock, par value $0.001 per share of Nextera
(the "Preferred Stock" and together with the Common Stock and taking into
account the considerations set forth in Section 4, below, the "Shares");

                  WHEREAS, the Shares represent approximately 71.45% of the
voting power of the issued and outstanding voting securities of Nextera; and

                  WHEREAS, to induce the execution of the Purchase Agreement by
Buyer, the Stockholders agree to vote the Shares so as to facilitate
consummation of the Transaction to the extent more fully described below.

                  NOW, THEREFORE, in consideration of the mutual promises and
the mutual covenants and agreements contained herein, the parties agree as
follows:

1.       Agreement to Vote Shares.

         1.1      At any meeting of the stockholders of Nextera called with
respect to the Transaction, the Purchase Agreement and the other transactions
contemplated thereby, and at any

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adjournment thereof, and with respect to any consent solicited with respect to
the Transaction, the Purchase Agreement and any of the other transactions
contemplated thereby, the Stockholders shall vote the Shares (a) in favor of
approval of the Transaction, the Purchase Agreement, the other transactions
contemplated thereby and any matter which could reasonably be expected to
facilitate the Transaction and such other transactions and (b) against (i)
approval of any Acquisition Proposal (as such term is defined in the Purchase
Agreement), (ii) approval of any proposal made in opposition to or in
competition with the consummation of the Transaction and against any merger,
consolidation, sale of assets, reorganization or recapitalization, with any
party other than Buyer and/or its affiliates, (iii) any amendment of the
Certificate of Incorporation or By-Laws of any of the Sellers or other proposal
or transaction involving any of the Sellers which amendment or other proposal or
transaction would in any manner impede, frustrate, prevent or nullify the
Transaction, the Purchase Agreement or any of the other transactions
contemplated by the Purchase Agreement, or (iv) any action or agreement which
would result in a breach of any representation, warranty or covenant of the
Sellers or Nextera set forth in the Purchase Agreement. The Stockholders may
vote on all other matters in a manner determined in their sole discretion ((i),
(ii) or (iii) and/or (iv), a "Counter Proposal").

         1.2      The Stockholders, as the holders of record or beneficial
owners of voting stock of Nextera, shall be present, in person or by proxy, at
all meetings of stockholders of Nextera and at any adjournment thereof so that
all Shares are counted for the purpose of determining the presence of a quorum
at such meetings. The Stockholders shall not enter into any agreement or
understanding with any person or entity to vote or give instructions in any
manner inconsistent with the terms of this Section 1. This Agreement is intended
to bind each Stockholder only with respect to the voting of the Shares as
Stockholders herein, and shall not prohibit the applicable Stockholders from
acting in accordance with his or her fiduciary duties as an officer or director
of Nextera or Sellers.

2.       Irrevocable Proxy. Concurrently with the execution of this Agreement,
the Stockholders agree to deliver to Buyer an irrevocable proxy in the form
attached hereto as Exhibit A (the "Proxy"), provided that the Proxy shall be
revoked only upon the Expiration Date (as defined below). The Proxy is
irrevocable and coupled with an interest in the obligations of the Stockholder.

3.       No Solicitation of Proxies. Each Stockholder agrees (solely in its
capacity as such) that neither it nor any of its subsidiaries nor any of the
officers and directors and representatives (including any investment banker,
attorney or accountant retained by it or any of its subsidiaries) of it or its
subsidiaries shall, and that it shall use its reasonable best efforts to cause
its and its subsidiaries' employees and other agents not to (and shall not
authorize any of them to) directly or indirectly, engage in any solicitation (as
defined in Regulation 14A of the Rules and Regulations promulgated by the
Securities and Exchange Commission pursuant to the Exchange Act) of other
stockholders of Nextera (a) against the Transaction, the Purchase Agreement, the
other transactions contemplated thereby or any matter that could reasonably be
expected to facilitate the Transaction and such other transactions or (b) in
favor of any Counter Proposal.

4.       Definition of Shares. For purposes of this Agreement, the term "Shares"
shall include: (i) all securities of Nextera (including, without limitation, all
shares of Common Stock and all Options) owned of record by the Stockholders as
of the date of this Agreement, as indicated on

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the signature page of this Agreement; and (ii) all additional securities of
Nextera of which the Stockholder acquires record ownership during the period
from the date of this Agreement through the Expiration Date, including, without
limitation, through the exercise or conversion of any options, warrants or other
rights to purchase shares of Common Stock and other securities convertible into,
or exercisable for shares of Common Stock. In the event of a stock dividend or
distribution, or any change in the Shares by reason of any stock dividend,
split-up, recapitalization, combination, exchange of shares or the like, the
term "Shares" shall be deemed to refer to and include the Shares as well as all
such stock dividends and distributions and any shares into which or for which
any or all of the Shares may be changed or exchanged.

5.       Transfers of Shares. Each Stockholder hereby agrees that, at all times
during the period commencing with the execution and delivery of this Agreement
until the Expiration Date, such Stockholder (a) shall not cause or permit the
Transfer (as defined below) of any Shares, or any interest in the Shares, to be
effected, and (b) shall not deposit (or permit the deposit of) any Shares in a
voting trust or grant any proxy, or enter into any voting agreement or similar
agreement or arrangement in contravention of the obligations of the Stockholders
under this Agreement with respect to the Shares. Each Stockholder further agrees
with, and covenants to, Buyer that such Stockholder shall not request that
Nextera register the Transfer of any certificate or uncertificated interest
representing any of the Shares, unless such Transfer is made in compliance with
this Agreement. For purposes of this Agreement, a person or entity shall be
deemed to have effected a "Transfer" of a security if such person or entity,
directly or indirectly: (i) sells, offers to sell, makes any short sales of,
pledges, encumbers, lends, hypothecates, enters into any type of equity swap or
hedging of, grants an option with respect to, transfers or disposes of such
security, any interest therein, or the economic consequences of ownership of
such security or (ii) enters into an agreement, contract or commitment providing
for the sale of, making any short sales of, pledge of, lending of, encumbrance
of, equity swap or hedging of, grant of an option with respect to, transfer of
or disposition of such security, any interest therein or the economic
consequences of ownership of such security, other than any such actions pursuant
to which such person or entity maintains all voting rights with respect to such
security.

6.       Representations and Warranties of the Stockholders. The Stockholders
hereby jointly and severally represent and warrant to Buyer as follows:

         6.1      Authority.

                  (a)      Each Stockholder is duly incorporated, validly
existing and in good standing under the laws of the State of Delaware.

                  (b)      Each Stockholder has all requisite power and
authority to enter into this Agreement and to consummate the transactions
contemplated hereby. The execution and delivery of this Agreement by each
Stockholder, and the consummation of the transactions contemplated hereby, has
been duly authorized by all necessary action on the part of each Stockholder.

                  (c)      This Agreement has been duly executed and delivered
by each Stockholder and constitutes a valid and binding obligation of each
Stockholder enforceable in accordance with its terms, subject to its
enforceability against Buyer and FTI and the effect of

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applicable bankruptcy, reorganization, insolvency, moratorium or similar laws
affecting creditors' rights generally and subject to the effect of general
principles of equity, including, without limitation, the possible unavailability
of specific performance or injunctive relief, regardless of whether considered
in a proceeding in equity or at law. The execution and delivery of this
Agreement does not, and the consummation of the transactions contemplated hereby
and compliance with the terms hereof will not, conflict with, or result in any
violation of or default (with or without notice or lapse of time or both) under
or the acceleration of any provision of any trust agreement, partnership
agreement, loan or credit agreement, note, bond, mortgage, indenture, lease or
other agreement, instrument, permit, concession, franchise, license, judgment,
order, notice, decree, statute, law, ordinance, rule or regulation applicable to
any of the Stockholders or to any of the property or assets of any of the
Stockholders.

                  (d)      No consent, approval, order or authorization of, or
registration, declaration or filing with, any court, administrative agency or
commission or other governmental authority or instrumentality, domestic, foreign
or supranational, is required by or with respect to any Stockholder in
connection with the execution and delivery of this Agreement or the consummation
by any Stockholder of the transactions contemplated hereby.

         6.2      The Shares. The Shares have not been pledged by the
Stockholders. The Stockholders own no capital stock of Nextera other than the
Shares. Except for this Agreement, no proxies or powers of attorney have been
granted with respect to the Shares that will remain in effect after the
execution of this Agreement. Except for this Agreement and the Proxy, no voting
arrangement (including voting agreement or voting trust) affecting the Shares
shall remain in effect after the execution of this Agreement.

7.       Effectiveness. The effectiveness of this Agreement is conditioned upon
the Purchase Agreement having been duly executed and delivered by all of the
parties thereto and the Purchase Agreement being in full force and effect.

8.       Termination. Notwithstanding anything else in this Agreement, this
Agreement, the Proxy and all obligations of each Stockholder under either this
Agreement or the Proxy shall automatically terminate as of the earlier to occur
of the following (such date, the "Expiration Date"): (i) such date and time as
the Purchase Agreement shall have been terminated in accordance with its terms,
(ii) such date and time as the Transaction shall become effective in accordance
with the terms and conditions of the Purchase Agreement or (iii) upon the
execution of a written agreement by all parties hereto.

9.       Additional Documents. Buyer and the Stockholders hereby covenant and
agree to execute and deliver any additional documents necessary, in the
reasonable determination of Buyer's legal counsel, to carry out the intent of
this Agreement.

10.      Legal Opinion. The Stockholders shall cause Buyer and FTI to receive an
opinion of Maron & Sandler in the form attached hereto as Exhibit B.

11.      Miscellaneous.

         11.1     Severability. If any term, provision, covenant or restriction
of this Agreement is held by a court of competent jurisdiction to be invalid,
void or unenforceable, the remainder of

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the terms, provisions, covenants and restrictions of this Agreement shall remain
in full force and effect and shall in no way be affected, impaired or
invalidated.

         11.2     Binding Effect and Assignment. This Agreement and all of the
provisions hereof shall be binding upon and inure to the benefit of the parties
hereto and their respective successors and permitted assigns, but, except as
otherwise specifically provided herein, neither this Agreement nor any of the
rights, interests or obligations of the parties hereto may be assigned by any of
the parties without the prior written consent of all of the other parties
hereto.

         11.3     Amendments and Modifications. This Agreement may not be
modified, amended, altered or supplemented except upon the execution and
delivery of a written agreement executed by the parties hereto.

         11.4     Specific Performance; Injunctive Relief. The parties hereto
acknowledge that each of the parties will be irreparably harmed and that there
will be no adequate remedy at law for a violation of any of the covenants or
agreements of the parties set forth herein. Therefore, it is agreed that, in
addition to any other remedies which may be available to any party upon a
violation by one or more other parties, such non-violating party shall have the
right to enforce such covenants and agreements by specific performance,
injunctive relief or by any other means available to it at law or in equity.

         11.5     Notices.

                  All notices, requests, claims, demands and other
communications hereunder shall be in writing and sufficient if delivered in
person, by commercial overnight courier service, by confirmed fax or sent by
mail (registered or certified mail, postage prepaid, return receipt requested)
to the respective parties as follows:

                  (a)      if to Buyer, to:

                           FTI Consulting, Inc.
                           2021 Research Drive
                           Annapolis, MD 21401
                           Attention: Theodore I. Pincus
                           Fax: 410-224-2809

                           with a copy to:

                           Paul, Hastings, Janofsky & Walker LLP
                           75 East 55th Street
                           New York, NY 10022-3205
                           Attention: Charles H. Baker, Esq.
                           Fax: (212) 319-4090

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                  (b)      if to the Stockholders, to:

                           Maron & Sandler
                           1250 Fourth Street, Suite 550
                           Santa Monica, CA 90401
                           Attention: James Banks, Esq.
                           Fax: (310) 570-4901

or to such other address as any party hereto may have furnished to the other
parties in writing in accordance herewith, except that notices of change of
address shall only be effective upon receipt.

         11.6     Governing Law. This Agreement shall be governed by, construed
and enforced in accordance with the laws of the State of New York applicable to
contracts to be executed and performed entirely within such State.

         11.7     Entire Agreement. This Agreement and the other agreements
referred to herein contain the entire understanding of the parties in respect of
the subject matter hereof and supersede all prior negotiations and
understandings between the parties with respect to such subject matter.

         11.8     Counterparts. This Agreement may be executed in counterparts,
each of which shall be an original, but all of which together shall constitute
one and the same agreement.

         11.9     Effect of Headings. The section headings herein are for
convenience only and shall not affect the construction or interpretation of this
Agreement.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

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                  IN WITNESS WHEREOF, the parties have caused this Agreement to
be duly executed on the day and year first above written.

                                          FTI CONSULTING, INC.

                                          By: /s/ Theodore I. Pincus
                                              ----------------------------------
                                              Name: Theodore I. Pincus
                                              Title: Executive Vice President
                                              and Chief Financial Officer

                                          LI ACQUISITION COMPANY, LLC

                                          By: /s/ Theodore I. Pincus
                                              ----------------------------------
                                              Name: Theodore I. Pincus
                                              Title: Executive Vice President
                                              and Chief Financial Officer

                                          NEXTERA ENTERPRISES HOLDINGS, INC.

                                          By: /s/ Stanley E. Maron
                                              ----------------------------------
                                              Name: Stanley E. Maron
                                              Title: Secretary

                                          KNOWLEDGE UNIVERSE, INC.

                                          By: /s/ Steven B. Fink
                                              ----------------------------------
                                              Name: Steven B. Fink
                                              Title: Treasurer and Vice Chairman

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                                   EXHIBIT A

                           FORM OF IRREVOCABLE PROXY
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                                    EXHIBIT B

                         FORM OF MARON & SANDLER OPINION