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                                                                    Exhibit 10.1

                     SEVERANCE AGREEMENT AND GENERAL RELEASE

      This Severance Agreement and General Release (this "Agreement") is entered
into by and between John A. de Armas (including all successors, assigns and
heirs, "Employee") and Centennial Communications Corp., and any and all of its
affiliates, subsidiaries, predecessors, successors and assigns and any of its
employees, directors, officers and shareholders (collectively "Employer").

                                    RECITALS

      A.    Employee resigned as an officer of Employer effective January 11,
            2005 (the "Resignation Date").

      B.    Employee and Employer wish to permanently resolve any and all claims
            and disputes, whether known or unknown, which exist or may exist on
            Employee's behalf, including but not limited to any claims arising
            out of Employee's employment with Employer and the termination of
            that employment.

      NOW THEREFORE, in exchange for the consideration, covenants and promises
contained herein, the receipt and sufficiency of which is hereby acknowledged,
Employer and Employee agree as follows:

      1.    As soon as practicable after the Resignation Date, Employer shall
            pay Employee the amounts set forth on Exhibit 1 hereto, subject to
            applicable tax withholdings. Employee acknowledges that Employee has
            been paid for any and all allowances or payments due and owing to
            Employee at the Resignation Date. Except as expressly provided
            herein, Employee acknowledges that he is not entitled to receive any
            vacation accrual or other payments or benefits after the Resignation
            Date.

      2.    Effective on the Resignation Date, Employee will cease to
            participate in any Employer sponsored plans and benefits, including
            without limitation any employee stock option plan, employee stock
            purchase plan and 401(k) plan. All funds previously contributed to
            any stock purchase plan will be returned to Employee in accordance
            with the terms of such plan.

      3.    Employee hereby irrevocably and expressly fully waives, releases,
            acquits and forever discharges Employer from any and all claims,
            charges, complaints, liabilities, allegations, demands, injuries,
            debts, breaches, violations, acts or omissions and causes of action,
            known or unknown, suspected or unsuspected, past or present,
            foreseen or unforeseen, in law or in equity which Employee now has,
            ever had or may hereafter have against Employer arising out of,
            directly or indirectly, or in any way relating to, Employee's
            employment with Employer or the termination of such employment,
            including any claims pursuant to any local, state,


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            federal, or other laws, statutes or regulations including without
            limitation, Commonwealth of Puerto Rico and Dominican Republic laws
            (collectively, "Claims").

      4.    Employee further covenants not to, directly or indirectly, bring any
            such Claims against Employer. Employee represents to Employer that
            he is the sole owner of any and all Claims that he is relinquishing
            by executing this Agreement and that no other person has any
            interest in any such Claims. Employee acknowledges that he has had
            the benefit of advice of competent legal counsel with respect to the
            decision to enter into this Agreement.

      5.    Employee represents and warrants to Employer that on or prior to the
            date hereof (except as set forth on Schedule 1 hereto), Employee has
            (i) returned to Employer all keys, vehicles, computers, telephones,
            beepers, inventory and/or any other property of Employer including
            any and all confidential and proprietary information that is in
            Employee's possession or control and will make no further use of
            same after the date hereof and (ii) repaid Employer all amounts
            owing to Employer on account of advances, other expenses or
            otherwise ("Owed Amounts"). Employee acknowledges and agrees that in
            order to recoup any Owed Amounts, Employer may set-off any Owed
            Amounts against any amounts to be paid by Employer to Employee
            hereunder. Employer hereby waives any rights it had to reimbursement
            by Employee of any Travel Payment (as defined in Section 5.1 of
            Employee's employment agreement).

      6.    Employee understands, acknowledges and agrees that he is waiving any
            and all Claims, which include without limitation, claims of wrongful
            discharge, breach of contract, lost wages, emotional distress,
            claims under Title VII of the Civil Rights Act of 1964, the Civil
            Rights Act of 1991, the Age Discrimination in Employment Act, as
            amended, the Americans with Disabilities Act, the Federal
            Rehabilitation Act of 1973, Employee Retirement Income Security of
            1974, as amended, the Equal Pay Act of 1963, claims of unjustified
            dismissal (Law 80 of May 30, 1976); benefits of any kind, damages of
            any kind, any claim on wages under Puerto Rico's Civil Code; all
            claims involving violations of the Employer's rules, policies and
            procedures; wage and salary claims; Act No. 96 of June 26, 1956; Act
            No. 223 of July 23, 1974, Act No. 289 of 1946; Act No. 180 of July
            27, 1998; Act No. 84 of August 1, 1995; Act No. 379 of May 15, 1948
            and Act No. 148 of June 30, 1969; discrimination on account of sex,
            religion, race, age, political ideas, social condition or origin,
            national origin, disability or any other reason prohibited by Puerto
            Rico Act No. 100 of June 30, 1959, Puerto Rico Act No. 69 of 1985,
            Puerto Rico Act No. 17 of April 22, 1988, Puerto Rico Act No. 3 of
            March 13, 1942, the Constitution of the Commonwealth of Puerto Rico,
            and any other Civil Rights laws; Family and Medical Leave Act;
            Federal Rehabilitation Act of


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            1973; Puerto Rico Act No. 44 of 1985; Puerto Rico Act No. 115 of
            December 20, 1991; the Workers' Compensation Law of Puerto Rico;
            Puerto Rico Act No. 45 of April 18, 1935; Puerto Rico Act No. 139 of
            June 26, 1956 (SINOT); the Insurance Code of Puerto Rico; the
            Occupational Safety and Health Act (OSHA); Puerto Rico Safety and
            Health Act of 1975 (PROSHA); the Consolidated Omnibus Budget
            Reconciliation Act of 1985 ("COBRA"); the Health Insurance
            Portability and Accountability Act of 1996; or under any other
            federal, state or Commonwealth of Puerto Rico or Dominican Republic
            law, including Article 1802 and 1803 of the Civil Code of Puerto
            Rico and all statutes on libel and defamation, malicious prosecution
            and further including without limitation any other federal, state or
            local laws and regulations relating to employment and/or employment
            discrimination, including any Commonwealth of Puerto Rico or
            Dominican Republic laws.

      7.    Each party hereto promises and agrees that, unless compelled by
            legal process, it will not disclose to any third party (including,
            without limitation, any present or former employee of Employer) and
            will keep confidential the fact or terms of this Agreement,
            including without limitation the amounts referred to in this
            Agreement. Each party hereto may disclose the terms contained herein
            to attorneys, accountants, immediate family members and other
            professional advisors to whom the disclosure is necessary to
            accomplish the purposes for which such party has contacted such
            advisors. Employer intends to file this Agreement with the
            Securities and Exchange Commission, to the extent required by
            applicable rules and regulations.

      8.    Employee acknowledges that due to the position Employee has occupied
            and the responsibilities Employee has had while employed by
            Employer, Employee has received confidential and proprietary
            information concerning Employer. Employee hereby promises and agrees
            that, unless compelled by legal process, Employee will not disclose
            to any third party and will keep confidential all such confidential
            and proprietary information received, developed or learned by
            Employee while employed by Employer, including without limitation
            information concerning Employer's products, procedures, policies,
            customers, sales, prices, financial information, technical
            information, network information, employee information, marketing
            strategies, and the terms of Employer's contracts with third
            parties. In addition, Employee agrees to delete from his laptop
            computer as soon as practicable following the date hereof, all
            confidential information relating to Employer.

      9.    Employee agrees that for a period of three years from the
            Resignation Date, he will not directly or indirectly induce or
            attempt to induce any employee of the Employer to leave the employ
            of the Employer. Employee agrees that he will not now, or in the
            future, deliberately


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            disrupt, damage, injure or interfere with the business of Employer.

      10.   Employee agrees that it will not now, or in the future, make any
            disparaging statements (whether oral or written) concerning
            Employer.

      11.   In exchange for the consideration to be received by Employee
            hereunder, which Employee expressly acknowledges is sufficient and
            satisfactory, Employee agrees that for a period of one year from the
            Resignation Date, Employee agrees that he will not, directly or
            indirectly, own, manage, control, participate in, consult with,
            render services for or in any manner engage in any business in the
            Service Area (as defined below) which shall compete with any
            business conducted by the Employer on the Resignation Date. For
            purposes of this covenant, the term Service Area means all
            geographic areas in which the Company and its subsidiaries operate
            on the Resignation Date. Employee acknowledges that he fully
            understands the scope and meaning of this non-compete provision and
            agrees that it is reasonable in light of the circumstances.

      12.   Employee hereby acknowledges and agrees that a violation of Section
            8, 9, 10 or 11 will cause irreparable injury to Employer and
            Employer will be entitled, in addition to any other rights and
            remedies Employer may have at law or in equity, to seek an
            injunction enjoining and restraining Employee from doing or
            continuing to do any such violative act.

      13.   This Agreement and any documents referred to herein shall, in all
            respects, be interpreted, enforced, and governed by and under the
            laws of the State of New Jersey.

      14.   Employee acknowledges that nothing herein shall be interpreted to be
            an admission of liability by Employer.

      15.   Employee agrees that all covenants contained in this Agreement shall
            survive its execution.

      16.   If any provision of this Agreement is deemed to be invalid or
            unenforceable, the remainder of the Agreement shall not be affected,
            and a suitable and equitable provision shall be substituted for the
            invalid and unenforceable provision in order to carry out, as far as
            may be valid and enforceable, the intent and purpose of such invalid
            or unenforceable provision.

      17.   Employee acknowledges and agrees that no promises or representations
            were made to Employee by any person which do not appear written
            herein and that Employee has not relied on any such promise or
            representation. This Agreement contains the entire agreement of the
            parties on the subject matter thereof. This Agreement may not be
            modified except by a writing


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            signed by the parties or as provided in paragraph 16. This Agreement
            may be executed in one or more counterparts, each of which will be
            deemed to be an original copy of this Agreement with signatures by
            fax counting for all purposes as original signatures.

      18.   Employee hereby acknowledges that Employee has read and understands
            this Agreement and that Employee signs this Agreement voluntarily,
            with full knowledge of any and all rights which he may have, and
            without coercion and was given the opportunity to review this
            Agreement with his attorney. Employee further acknowledges that the
            waivers Employee has made in this Agreement are knowing, conscious
            and voluntary and are made with full appreciation that Employee is
            forever foreclosed from pursuing any of the claims so waived. After
            having sufficient time to carefully read all the terms and
            conditions of this Agreement, Employee affirms that he completely
            understands the same, as well as their consequences. Employee
            expressly acknowledges that he has been informed that he can, and
            must, seek legal counsel before signing this Agreement, and that a
            reasonable time of at least twenty-one (21) days has been given to
            read, examine, evaluate and seek legal counsel. If the Employee
            signs this Agreement prior to the expiration of the twenty-one (21)
            day period, the remainder of the period will be deemed as
            voluntarily and expressly waived by the Employee. The parties agree
            that Employee has a period of seven (7) days from the date this
            Agreement is signed to revoke the same. For such reason, the parties
            agree that any payments to be made to Employee hereunder will be
            made after the seven (7) day period has expired.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
date set forth below.

JANUARY 19, 2005

CENTENNIAL COMMUNICATIONS CORP.

By: /s/ Michael J. Small
Title:   Chief Executive Officer

JOHN A. DE ARMAS

By: /s/ John de Armas


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                                    EXHIBIT 1

1.    Side Letter. Benefits and other compensation described in letter agreement
      dated the date hereof and attached hereto.

2.    Base Salary. Nine (9) months base salary ($213,750) to be paid to Employee
      over a 9-month period following the Transition Period (as defined in the
      Side Letter), in accordance with the Employer's customary payroll
      practices and subject to applicable tax withholdings.

3.    Medical Benefits. Employer will continue to cover Employee under its
      medical and dental benefits programs in accordance with prior practice and
      subject to customary Employee contributions until the earlier to occur of
      (i) the 1-year anniversary of the Resignation Date or (ii) the date that
      Employee has obtained similar benefits from a subsequent employer.
      Employee will notify Employer promptly upon the occurrence of clause (ii)
      above.

4.    Bonus. Employee shall be paid his accrued bonus for fiscal year 2005 in
      the aggregate amount of $166,667, at such time as other executive officers
      of Employer are paid their fiscal year 2005 bonuses.

5.    Miscellaneous Costs. Employee shall be reimbursed in an amount not to
      exceed $10,000 for his actual and documented costs incurred in connection
      with relocation, job placement and other similar transition costs. All
      receipts for such expenses must be submitted to the Chief Executive
      Officer prior to May 31, 2005.

6.    Reimbursement of Business Expenses. Employer shall reimburse Employee for
      any and all outstanding reasonable business expenses in accordance with
      Employer's policies incurred by Employee through the Resignation Date.

7.    Personal Property. Employee shall be permitted to maintain possession of
      his laptop computer and his wireless telephone. Employee will begin paying
      monthly charges on such wireless phone, effective April 15, 2005.


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                         CENTENNIAL COMMUNICATIONS CORP.

January 19, 2005


Dear Mr. de Armas:

This letter is being delivered to you in connection with the Severance Agreement
and General Release (the "Release Agreement") dated the date hereof. Capitalized
terms used herein and not defined herein have the meanings given to such terms
in the Release Agreement.

Notwithstanding any provision in the Release Agreement to the contrary, during
the period of time from the Resignation Date to the 3-month anniversary of the
Resignation Date (the "Transition Period"), Employee shall continue as an
employee of Employer. In consideration for the services to be performed by
Employee to Employer during the Transition Period, Employee shall continue to
receive payment of his current base salary at a rate of $285,000 per annum (or
$71,250 for such 3-month period), paid bi-weekly in accordance with past
practice. In addition, during the Transition Period, Employee may exercise any
stock options in accordance with the terms of his option agreements. Except as
expressly provided herein or in the Release Agreement (including the exhibits),
Employee shall be entitled to no other compensation or other payments from
Employer.

Employee has voluntarily elected during the Transition Period that he does not
wish to participate in Employer's 401K plan, stock purchase plan or any other
Employee benefit plan.

On the 3-month anniversary of the Resignation Date, Employee shall, without any
further action on the part of Employee or Employer, be deemed to have been
terminated from the employ of Employer (such date being referred to as the
"Termination Date"). Accordingly, Employee shall have three months from the
Termination Date to exercise any vested stock options.


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During the Transition Period, Employee agrees to make himself available to
Employer for such purposes as Employer may reasonably request. During the
Transition Period, Employee agrees that he (1) is not an officer of Employer,
(2) has no authority to bind Employer to any contract or agreement (whether oral
or written) or to assume or create any obligation or responsibility, express or
implied, on behalf of or in the name of Employer and (3) will not hold himself
out as having any such authority.

CENTENNIAL COMMUNICATIONS CORP.

By: /s/  Michael J. Small
Title:    Chief Executive Officer

Accepted and Agreed
as of the date first above written


JOHN DE ARMAS

By: /s/ John de Armas


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