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                                                                   Exhibit 10.1

                        EXECUTIVE EMPLOYMENT AGREEMENT
                        ------------------------------


     This Executive Employment Agreement is made as of this eighth day of
January, 2000, by and between Focal Communications Corporation and its
Subsidiaries, a Delaware corporation (the "Company") and Michael L. Mael whose
address is 9 Winterset Court, Potomac, MD 20854 (the "Executive").

     WHEREAS, the Company and the Executive wish to enter into an agreement for
employment which shall provide certain terms of employment. The parties
acknowledge that all terms of employment may not be contained in this Agreement,
but that as to other conflicting terms of employment, which may be initiated
from time to time by the Company, the terms contained herein, or as amended from
time to time by the parties hereto, shall control.

     NOW THEREFORE, in accordance with the premise above, the parties agree as
follows:

     1.   Terms of Executive's Employment.
          -------------------------------

          (a)  Employment. The Company hereby employs Executive, and Executive
               ----------
               hereby accepts employment and agrees to perform his duties and
               responsibilities hereunder, in accordance with the terms and
               conditions hereinafter set forth. The Company shall have the
               right to terminate the Executive's employment for any reason, at
               any time, with or without Cause (defined below). Executive shall
               have the right to terminate his employment for any reason,
               including Good Reason (as hereinafter defined), at any time, upon
               giving the Company written notice two weeks prior to such
               termination.

          (b)  Duties and Responsibilities.
               ---------------------------

               (i)  Initially, the Executive shall serve as Executive Vice
                    President of the Company and the President of [subsidiary],
                    and so long as Executive is employed by the Company or any
                    of its Subsidiaries, the Executive shall serve in such
                    position as may be determined by the Board of Directors
                    ("Board") and shall perform all duties and accept all
                    responsibilities incident to such position or as may be
                    assigned to him by the Board, and shall at all times comply
                    with the policies and procedures adopted by the Company for
                    its employees.

               (ii) The Executive represents and covenants to the Company that
                    he is not subject or a party to any employment agreement,
                    non-competition agreement, nondisclosure agreement or any
                    similar agreement, covenant or restriction that would
                    prohibit the Executive from executing this Agreement and
                    performing his duties and responsibilities assigned by the
                    Company.
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          (c)  Extent of Service. So long as Executive is employed by the
               -----------------
               Company or any of its Subsidiaries, the Executive agrees to use
               his best efforts to carry out his duties and responsibilities
               under paragraph 1 (b) hereof and to devote his full professional
               time and attention thereto.

          (d)  Base Compensation. For all the services rendered by the Executive
               -----------------
               hereunder, the Company shall, commencing on the agreed upon start
               date of January 10, 2000, and continuing so long as Executive is
               employed by the Company or any of its Subsidiaries, pay the
               Executive an annual salary at the rate of $225,000 per year, plus
               any additional amounts, if any, as may be approved by a majority
               of the Board, less withholding required by law or agreed to by
               the Executive, and payable in installments at such times as is
               customary with the Company but in any event no less frequently
               than monthly. The Company agrees that the Executive's salary will
               be reviewed annually by the Board to determine if any adjustment
               is appropriate. For purposes of paragraph 1 (f) and Section 3
               herein, Executive's annual salary shall not be less than
               $225,000. So long as Executive is employed by the Company or any
               of its Subsidiaries, the Executive shall also be entitled to
               participate in such vacation pay and any other fringe benefit
               plans as may from time to time be adopted by a majority of the
               Board and as are made available generally to other senior
               executives of the Company.

          (e)  Incentive Compensation. In addition to the compensation set
               ----------------------
               forth in paragraph 1 (d) above, so long as the Executive is
               employed by the Company or its Subsidiaries the Executive shall
               be entitled to participate in a discretionary annual bonus plan
               providing for the payment to Executive of an annual bonus, in an
               amount to be determined by a majority of the Board or another
               officer of the Company as the Board determines. Executive shall
               be entitled to provide his input on the terms of his annual bonus
               plan before it is submitted to the Company's Board, but Executive
               acknowledges that such plan is discretionary in nature and is
               determined in the exclusive discretion of the Board or other
               officer so designated by the Board. The Company may adopt from
               time to time a bonus program, in which the Executive shall
               participate, the terms of which require the Company to achieve
               certain performance goals which are set in advance each year in
               the sole discretion of the Board.

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          (f)  Severance Pay. If at any time after the date hereof Executive
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               ceases to be employed by the Company and its Subsidiaries
               ("Termination") for death or disability or by the Company for any
               reason other than Cause, or by Executive for Good Reason (a
               "Covered Termination"), Executive (or, in the case of death,
               Executive's estate) shall, until the end of the Severance Pay
               Period (as defined below), be entitled to receive a salary at the
               same rate of pay as, and on the same schedule and terms as was
               customary for, the salary Executive received under paragraph 1
               (d) above immediately prior to the Termination, as well as
               (except in the case of Executive's death) comparable medical
               benefits to those provided by the Company to Executive
               immediately prior to the Termination (such salary and benefits
               collectively, the "Severance Pay"); provided that if at any time
               during the Severance Pay Period Executive obtains other
               employment, Executive's Severance Pay shall during the period of
               such employment be reduced (but not below zero) by the amount of
               salary and benefits Executive receives as compensation for such
               employment; (ii) all restricted stock theretofore granted to
               Executive shall vest immediately; and (iii) all stock options
               theretofore granted to Executive and scheduled to vest within 12
               months of the Covered Termination shall vest immediately. The
               payment of such Severance Pay shall in no way be construed as a
               continuation of Executive's employment after the Termination. The
               "Severance Pay Period" shall be equal to (i) if Executive is
               terminated by the Company for any reason other than Cause, the
               longer of (A) the period between the Covered Termination and the
               12-month anniversary of the start date of employment of
               Executive, and (B) the 6-month period commencing on the date of
               the Covered Termination, or (ii) if Executive's employment is
               terminated due to Good Reason, death or disability, the 6-month
               period commencing on the date of the Covered Termination. If
               Executive resigns other than for Good Reason or is terminated by
               the Company for Cause, the Company shall not be obligated to pay
               any Severance Pay or provide vesting of any restricted stock or
               stock options as provided in this paragraph.

          (g)  Nondisclosure and Nonuse of Confidential Information.
               ----------------------------------------------------

               (i)  Nondisclosure Obligation. Executive shall not disclose or
                    ------------------------
                    use at any time, either during his employment with the
                    Company or thereafter, any Confidential Information (as
                    defined below) of which Executive is or becomes aware,
                    whether or not such information is developed by him except
                    to the extent that such disclosure or use is directly
                    related to and required by Executive's performance of duties
                    assigned to Executive by the Company. Executive shall take
                    all appropriate steps to safeguard Confidential Information
                    and to protect it against disclosure, misuse, espionage,
                    loss and theft.

               (ii) Confidential Information. As used in this Agreement, the
                    ------------------------
                    term "Confidential Information" means information that is
                    not generally known to the public and that is used,
                    developed or obtained by the Company in connection with its
                    business, including but not limited to (i) products or
                    services, (ii) fees, costs and pricing structures, (iii)
                    designs,

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                    (iv) analysis, (v) drawings, photographs and reports, (vi)
                    computer software, including operating systems, applications
                    and program listings, (vii) flow charts, manuals and
                    documentation, (viii) data bases, (ix) accounting and
                    business methods, (x) inventions, devices, new developments,
                    methods and processes, whether patentable or unpatentable
                    and whether or not reduced to practice, (xi) customers and
                    clients and customer or client lists, (xii) copyrightable
                    works, (xiv) all technology and trade secrets, (xv) business
                    plans and financial models, and (xvi) all similar and
                    related information in whatever form. Confidential
                    Information shall not include any information that has been
                    published in a form generally available to the public prior
                    to the date Executive proposes to disclose or use such
                    information. Information shall not be deemed to have been
                    published merely because individual portions of the
                    information have been separately published, but only if all
                    material features constituting such information have been
                    published in combination.

          (h)  Cause. Cause means a finding by 2/3rds of the Board members then
               -----
               serving, after Executive has been given the opportunity for a
               formal hearing, of (A) Executive's theft or embezzlement, or
               attempted theft or embezzlement, of money or property of the
               Company, Executive's perpetration or attempted perpetration of
               fraud, or Executive's participation in a fraud or attempted
               fraud, on the Company, or Executive's unauthorized appropriation
               of, or attempt to misappropriate, any tangible or intangible
               assets or property of the Company, (B) any act or acts of
               disloyalty, misconduct or moral turpitude by Executive injurious
               to the interest, property, operations, business or reputation of
               the Company or Executives' conviction of a crime the commission
               of which results in injury to the Company, or (C) Executive's
               refusal or failure (other than by reason of disability) to carry
               out reasonable instructions by his superiors or the Board and in
               the case of subsection (C), the failure of Executive to cure the
               same within 10 business days, after receipt of written notice
               thereof from the Company.

          (i)  Good Reason. "Good Reason" means (A) a significant adverse change
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               by the Company in the nature or scope of the duties attached to
               Employee's positions as Executive Vice President and President,
               respectively, (B) the willful failure or refusal of Company to
               perform its material obligation under Section 1(d) or (e) of this
               Agreement, or (C) the reduction by the Company of its
               expenditures for the operation of the Company's Data Services
               business in an amount that is materially less than the
               expenditures set forth in the Company's fiscal year 2000 budget
               unless such reduction is part of a reduction applicable generally
               to the Company's other operating units, or (D) the Company
               requires the Executive to have his principal location of work
               changed to a location which is in excess of 50 miles from
               Washington, D.C. without Executive's prior written consent, and,
               in the case of subsections (A), (B) or (C), the failure of the
               Company to cure the same within 10 business days after receipt of
               written notice thereof from Executive.

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     2.   The Company's Ownership of Intellectual Property.
          ------------------------------------------------

          (a)  Acknowledgment of Company Ownership. In the event that Executive
               -----------------------------------
               as part of his activities on behalf of the Company generates,
               authors or contributes to any invention, design, new development,
               device, product, method or process (whether or not patentable or
               reduced to practice or constituting Confidential Information),
               any copyrightable work (whether or not constituting Confidential
               Information) or any other form of Confidential Information
               relating directly or indirectly to the Company's business as now
               or hereinafter conducted (collectively, "Intellectual Property"),
               Executive acknowledges that such Intellectual Property is the
               exclusive property of the Company and hereby assigns all right,
               title and interest in and to such Intellectual Property to the
               Company. Any Intellectual Property that is copyrightable work
               prepared in whole or in part by Executive will be deemed "a work
               made for hire" under Section 201(b) of the 1976 Copyright Act,
               and the Company shall own all of the rights comprised by the
               copyright therein. Executive shall promptly and fully disclose to
               the Company all Intellectual Property he generates, authors or
               contributes to the Company and shall cooperate with the Company
               to protect the Company's interests in and rights to such
               Intellectual property (including, without limitation, providing
               reasonable assistance in securing patent protection and copyright
               registrations and executing all documents as reasonably requested
               by the Company, whether such requests occur prior to or after
               Termination of Executive's employment with the Company).

          (b)  Executive Invention. Executive understands that paragraph 2 of
               -------------------
               this Agreement regarding the Company's ownership of Intellectual
               Property does not apply to any invention for which no equipment,
               supplies, facilities or trade secret information of the Company
               were used and which was developed entirely on Executive's own
               time, unless (i) the invention relates to the business of the
               Company or to the Company's actual or demonstrably anticipated
               research or development or (ii) the invention results from any
               work performed by Executive for the Company.

          (c)  Delivery of Materials upon Termination of Employment. As
               ----------------------------------------------------
               requested by the Company from time to time and upon the
               Termination of Executive's employment with the Company for any
               reason, Executive shall promptly deliver to the Company all
               copies and embodiments, in whatever form, of all Confidential
               Information and Intellectual Property in Executive's possession
               or within his control (including, but not limited to, written
               records, notes, photographs, manuals, notebooks, documentation,
               program listings, flow charts, magnetic media, disks, diskettes,
               tapes and all other materials containing any Confidential
               Information or Intellectual Property) irrespective of the
               location or form of such material and, if requested by the
               Company shall provide the Company with written confirmation that
               all such materials have been delivered to the Company.

     3.   Noncompetition and Nonsolicitation.
          ----------------------------------

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          (a)  Noncompetition. Executive acknowledges and agrees with the
               --------------
               Company that Executive's services to the Company are unique in
               nature and that the Company would be irreparably damaged if
               Executive were to provide similar services to any person or
               entity competing with the Company or engaged in a similar
               business. For and in consideration of the terms contained herein
               Executive covenants and agrees with the Company that during the
               Noncompetition Period (as defined below), Executive shall not,
               directly or indirectly, either for himself or for any other
               individual, corporation, partnership, joint venture or other
               entity, participate in any business division, group or franchise
               (or if there are no divisions, any business) where such division,
               group or franchise (or business, if applicable) engages or
               proposes to engage in any business conducted by the Company or
               proposed to be conducted pursuant to a Board resolution or
               Subsequent Business Plan (including, but not limited to, the sale
               or distribution of local switched dial tone telecommunication
               services) in any metropolitan statistical area ("MSA") in which
               the Company conducts such business or proposes to conduct such
               business pursuant to a Board resolution or Subsequent Business
               Plan. For purposes of this Agreement, the term "participate in"
               shall include, without limitation, having any direct or indirect
               interest in any corporation, partnership, joint venture or other
               entity, whether as a sole proprietor, owner, stockholder,
               partner, joint venturer, creditor or otherwise, or rendering any
               direct or indirect service or assistance to any individual,
               corporation, partnership, joint venture and other business entity
               (whether as a director, officer, manager, supervisor, employee,
               agent, consultant or otherwise), other than ownership of up to 2%
               of the outstanding stock of any class which is publicly traded.

          (b)  Nonsolicitation. During the Noncompetition Period, Executive
               ---------------
               shall not (i) induce or attempt to induce any employee of the
               Company to leave the employ of the Company, or in any way
               interfere with the relationship between the Company and any
               employee thereof, (ii) hire directly or through another entity
               any person who was an employee of the Company at any time during
               the Noncompetition Period, or (iii) induce or attempt to induce
               any customer, supplier, licensee or other business relation of
               the Company to cease doing business with the Company, or in any
               way interfere with the relationship between any such customer,
               supplier, licensee or relation and the Company (including,
               without limitation, making any negative statements or
               communications concerning the Company).

          (c)  Noncompetition Period. The "Noncompetition Period" shall commence
               ---------------------
               on the date hereof and continue (i) if Executive is terminated by
               the Company with or without Cause, until such date as shall be
               specified by the Company in writing within 14 calendar days after
               Termination, provided that such date shall not be later than the
               first anniversary of the Termination, or (ii) otherwise, until
               such date as shall be specified by the Company in writing within
               the 30 calendar days after Termination, provided that such date
               shall not be later than the 18-month anniversary of the
               Termination. After the end

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               of the Severance Pay Period (or if there is no Severance Pay, the
               date upon which the Company elects the duration of the
               Noncompetition Period), the Company shall until the end of the
               Noncompetition Period pay Executive his Noncompete Compensation
               (unless Executive breaches his obligations under this paragraph
               3, it being understood that in such case Executive shall continue
               to be bound by such obligations as if the Company were continuing
               to pay Noncompete Compensation). If there is no Severance Pay,
               the Company shall during the period from Termination until such
               time as the Company elects the duration of the Noncompetition
               Period (the "Interim Period"), pay Executive his Interim
               Compensation (unless Executive breaches his obligations under
               this paragraph 3, it being understood that in such case Executive
               shall continue to be bound by such obligations as if the Company
               were continuing to pay Interim Compensation). "Noncompete
               Compensation" shall consist of 50% of the salary that Executive
               received under paragraph 1 (d) above as compensation from the
               Company and its Subsidiaries immediately prior to termination
               (Executive's "Previous Salary") together with the continuation of
               the medical benefits that the Company provided to Executive
               immediately prior to Termination (Executive's "Previous
               Benefits"); provided that if at any time during the
               Noncompetition Period Executive obtains other employment (i) with
               comparable medical benefits to Executive's Previous Benefits,
               Executive's Noncompete Compensation shall during the period of
               such employment not include the continued provision of medical
               benefits, and (ii) with a salary exceeding 50% of Executive's
               Previous Salary, Executive's Noncompete Compensation shall during
               the period of such employment be reduced (but not below zero) by
               the amount of such excess. "Interim Compensation" shall consist
               of 100% of Executive's Previous Salary and Previous Benefits,
               provided that if at any time during the Interim Period Executive
               obtains other employment, Executive's Interim Compensation shall
               during the period of such employment be reduced (but not less
               than zero) by the amount of salary and benefits received as
               compensation for such other employment.

     4.   Notices. Any notice provided for in this Agreement must be in writing
          -------
          and must be either personally delivered, mailed by first class mail
          (postage prepaid and return receipt requested) or sent by reputable
          overnight courier service (charges prepaid) to the recipient at the
          address below indicated:

          To the Company: Focal Communications Corporation
                          200 N. LaSalle Street
                          Chicago, IL 60601
                          ATTN: Vice President, Human Resources

          with a copy to: Focal Communications Corporation
                          200 N. LaSalle Street
                          Chicago, IL 60601
                          ATTN: General Counsel

          To Executive:



     or to such other address or to the attention of such other person as the
     recipient party shall

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     have specified by prior written notice to the sending party. Any notice
     under this Agreement shall be deemed to have been given when personally
     delivered, one business day after being sent by reputable overnight courier
     service, or three business days after being deposited in the U.S. mail.

     5.   General Provisions.
          ------------------

          (a)  Severability. Whenever possible, each provision of this Agreement
               ------------
               shall be interpreted in such manner as to be effective and valid
               under applicable law, but if any provision of this Agreement is
               held to be invalid, illegal or unenforceable in any respect under
               any applicable law or rule in any jurisdiction, such invalidity,
               illegality or unenforceability shall not affect any other
               provision or any other jurisdiction as if such invalid, illegal
               or unenforceable provision had never been contained herein.

          (b)  Complete Agreement. This Agreement, those documents expressly
               ------------------
               referred to herein and other documents of even date herewith
               embody the complete agreement and understanding among the parties
               and supersede and preempt any prior understandings, agreements or
               representations by or among the parties, written or oral, which
               may have related to the subject matter hereof, in any way.

          (c)  Counterparts. This Agreement may be executed in separate
               ------------
               counterparts, none of which need contain the signature of more
               than one party hereto but each of which shall be deemed to be an
               original and all of which taken together shall constitute one and
               the same agreement.

          (d)  Successors and Assigns. Except as otherwise provided herein, this
               ----------------------
               Agreement shall bind the parties hereto and their respective
               successors and assigns and shall inure to the benefit of and be
               enforceable by the parties hereto and their respective successors
               and assigns.

          (e)  Choice of Law. All questions concerning the construction,
               -------------
               validity, enforcement and interpretation of this Agreement and
               the exhibits hereto shall be governed by the laws of the State of
               Illinois.

          (f)  Remedies. Each of the parties to this Agreement shall be entitled
               --------
               to enforce its rights under this Agreement specifically, to
               recover damages and cost (including reasonable attorney's fees)
               caused by any breach of any provision of this Agreement and to
               exercise all other rights existing in its favor. The parties
               hereto agree and acknowledge that money damages would not be an
               adequate remedy for any breach of the provisions of this
               Agreement and that any party may in its sole discretion apply to
               any court of law or equity of competent jurisdiction (without
               posting any bond or deposit) for specific performance and/or
               other injunctive relief in order to enforce or prevent any
               violations of the provisions of this Agreement.

          (g)  Amendment and Waiver. The provisions of this Agreement may be
               --------------------
               amended

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               and waived only with the prior written consent of the Company and
               Executive.

          (h)  Business Days. If any time period for giving notice or taking
               -------------
               action hereunder expires on a day which is a Saturday, Sunday or
               legal holiday in the State of Illinois, the time period will be
               automatically extended to the business day immediately following
               such Saturday, Sunday or holiday.


     IN WITNESS WHEREOF, the parties hereto have executed this Agreement on the
date first written above.



FOCAL COMMUNICATIONS CORPORATION



By: /s/ Robert C. Taylor, Jr.
   --------------------------

Its: President and Chief Executive Officer



EXECUTIVE:

/s/ Michael L. Mael
______________________________________

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