EXHIBIT 4.37
                                                                    ------------

                              [FLEXTECH LETTERHEAD]

Mark W Luiz
165 Cranley Gardens
London  N10

3 March 2000



Dear Mark

Service Agreement

We refer to the Service Agreement between ourselves dated February 1996 (the
"Service Agreement").

We hereby amend the Service Agreement as follows:-

(i)      in the event of the offer relating to the proposed merger ("Merger")
         between the Company and Telewest Communications plc ("Telewest")
         becoming unconditional, you will be appointed as Deputy Director of
         Content and New Media of the combined Flextech/Telewest group (the
         "Combined Group") on completion of the Merger; and

(ii)     in the event that you have not been offered a place on the board of
         directors of the Combined Group by 31 December 2000, the Company will
         make a payment of (pound)500,000 to you.

Should the offer relating to the Merger not become unconditional, the terms of
the Service Agreement, as in force prior to the execution of this letter, will
remain unchanged.

Other than as set out in this letter, there are no changes to the Service
Agreement.

Please could you acknowledge receipt of this letter and agreement to its terms
by signing and returning the enclosed copy letter. The date of signature by you
shall be the date on which this letter shall come into full force and effect.

Yours sincerely


/s/ Adam Singer
----------------
for and on behalf of                                 /s/ Mark Luiz
Flextech plc                                         ------------------
                                                     Mark Luiz

<PAGE>

THIS AGREEMENT is made the       day of        One thousand nine hundred and
ninety five

BETWEEN

(1)      FLEXTECH plc ("the Company") whose registered office is at The
         Quadrangle Imperial Square Cheltenham Gloucestershire GL50 1YX

and

(2)      MARK WALTER LUIZ ("the Executive") of 165 Cranley Gardens  London  N10

NOW IT IS HEREBY AGREED that the Company shall employ the Executive and the
Executive shall serve the Company upon and subject to the following terms and
conditions:-

1.       Definitions and Interpretation
         ------------------------------

1.1      In this Agreement

         "the Act"            means the Employment Protection (Consolidation)
                              Act 1978 (as amended)

         "Associated Company" means a company which is from time to
                              time a subsidiary or a holding company (as those
                              expressions are defined by s.736 Companies Act
                              1985) of the Company or a subsidiary (other than
                              the Company) of a holding company of the Company

         "Bank Holidays"      means and includes any day upon which the Banks in
                              England and Wales are not open for the transaction
                              of all normal banking business and (for the
                              avoidance of doubt) such term includes Saturdays
                              and the term "Public Holidays" shall have the same
                              meaning as Bank Holidays

         "the Board"          means the board of directors from time to time of
                              the Company

         "calendar month"     means each period of one month beginning on the
                              first and ending on the last day of each month

         "calendar year"      means each period of one year beginning on 1st
                              January and ending on 31st December in the same
                              year

         "the Companies Acts" means the Companies Acts 1985 to 1989

         "the Group"          means the Company and its associated companies

         "a Group Company"    means a company within the Group

         "Working Days"       means any day other than a Saturday or a Sunday
                              which is not a Bank Holiday or a Public Holiday


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<PAGE>

1.2      Any reference to a statutory provision shall be deemed to include a
         reference to any statutory modification or re-enactment of the same
         from time to time

1.3      Clause headings are used for ease of reference only and shall not
         affect the construction thereof

2.       Term of Appointment
         -------------------

2.1      The employment of the Executive on the terms of this Agreement shall
         continue (subject to termination as hereinafter provided) unless and
         until determined by either party giving to the other not less than
         twelve (12) months' written notice of termination expiring on the last
         day of a calendar month

2.2      If the Executive's employment is terminated by either party pursuant to
         clause 2.1 the Executive will have no right to work for the Company
         during the period of notice (although the Company will have power to
         require him to do so). If at the commencement of the period of notice
         or at any time during the period of notice the Executive is informed
         (whether by the Company, the Board or the Group Chief Executive) that
         he is not required to work for the Company during the remainder of the
         notice period then he shall become immediately entitled to receive in
         one lump sum the balance of monies that would have been paid to him
         during such period of notice had he worked for the Company during such
         period of notice and the Executive shall be free immediately to take up
         alternative employment

2.3      If the Executive's employment is terminated for any reason any share
         options to which he has become entitled pursuant to and during the
         course of his employment by the Company shall be deemed to be, and be,
         immediately exercisable by the Executive provided that if such exercise
         would aversely affect any favourable tax status of the Company's share
         option schemes instead the Company shall in consultation with the
         Executive provide the Executive with a benefit of equivalent economic
         value to the Executive

2.4      The Executive's employment from September 12th 1988 to the date hereof
         counts as part of the Executive's continuous period of employment with
         the Company

3.       Duties of the Executive
         -----------------------

3.1      During the period of his employment hereunder the Executive shall serve
         the Company as Chief Financial Officer and Company Secretary of the
         Company and shall be based at Twyman House 16 Bonny Street London
         provided that the Board (or its duly authorised nominee) may from time
         to time require the Executive to serve the Company in some other
         capacity or capacities involving duties carrying a comparable degree of
         responsibility and status in addition to and/or in substitution for the
         capacity referred to

3.2      The Executive shall if so requested by the Board (without any further
         remuneration than is hereinafter mentioned) perform such services for
         any Associated Company and accept such offices in any Associated
         Company as the Board may reasonably require

3.3      During the continuance of the employment hereunder the Board shall be
         at liberty from time to time to appoint any other person to act jointly
         with the Executive and in the event that the Executive is unable
         through illness accident or any other incapacity to carry out his
         duties under this Agreement for any consecutive period of three months
         the Company may (without prejudice to the provisions of clause 10)
         temporarily employ any person or


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<PAGE>

         persons to perform those duties in the Executive's place until such
         time as the Executive is able to resume the performance of his duties

3.4      The Executive shall unless prevented by injury or ill health devote the
         whole of his time attention and abilities to the business of the
         Company and shall well and faithfully serve the Company and the Group

3.5      The Executive shall carry out his duties hereunder between the hours of
         9.00 am and 5.00 pm on normal Working Days and during such other hours
         as may from time to time be necessary in order to fulfil properly his
         duties hereunder and he shall not be entitled to extra remuneration for
         work performed outside normal working hours

3.6      The Board shall have the right upon reasonable grounds from time to
         time to:-

         3.6.1    vary the place of the employment of the Executive within
                  England

         3.6.2    direct the Executive to visit such place or places (including
                  places outside the United Kingdom) as the Board may reasonably
                  require

         and the Company shall in such event reimburse to the Executive such
         removal and other expenses as the Executive may reasonably and with the
         prior approval of the Board incur in consequence thereof

3.7      The Executive shall be entitled to assume that any instruction or
         authorisation received from the Group Chief Executive represents a
         decision and/or request of the Board and is given with the authority of
         the Board

4.       Remuneration and Expenses
         -------------------------

4.1      The remuneration of the Executive shall be a fixed salary (inclusive of
         any fees payable to him as a director of any Associated Company)
         payable by equal monthly instalments in arrears on the last day of each
         month with such increments thereto as the Company may from time to time
         determine. The Executive's salary at the date hereof is One hundred and
         thirty thousand pounds per annum ((pound)130,000 p.a.)

4.2      The salary shall be reviewed by the Board during each calendar year of
         the term of this Agreement and shall be increased (but not decreased)
         with effect from 1st January in each such calendar year by such amount
         as the Board shall in its absolute discretion determine

4.3      In addition to the salary paid to the Executive pursuant to clause 4.1
         above the Executive shall be entitled to a bonus in respect of each
         calendar year of his employment by the Company (the "Bonus"). The
         amount of each Bonus shall be at the discretion of the Board. The
         Executive shall be entitled to be informed of the amount of and receive
         such Bonus by March 31st following the end of the calendar year in
         respect of which the bonus is paid

4.4      Further the Executive shall be entitled during the course of his
         employment to benefits in line with the Company's policy from time to
         time provided that under no circumstances shall such benefits
         (including without prejudice to the generality permanent health
         insurance, private medical insurance, life insurance, the right to
         participate in the Company's executive share option schemes and payment
         of home telephone bills) be less than the benefits paid to the
         Executive at the date hereof


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<PAGE>

4.5      The Company shall reimburse to the Executive all reasonable travelling
         hotel and other expenses incurred by him in or about the performance of
         his duties hereunder (including any expenses incurred in attending
         meetings of the Board or committees of the Board or general meetings of
         the Company or of any Associated Companies) subject to such expenses
         being submitted and evidenced in such manner as the Company shall
         specify from time to time

5.       Motor Car
         ---------

5.1      To assist him in the performance of his duties hereunder the Company
         shall during the term of his employment hereunder (subject to his being
         fully qualified to drive) provide the Executive with a motor car of a
         model and type to be agreed between the Executive and the Group Chief
         Executive (subject to its being suitable for use by a person of his
         status) and at the Company's cost and expense shall permit him to use
         it for his own private purposes including use on holidays. The Company
         shall from time to time at its own cost and expense replace the same
         with another car of a type similar to and of a value equivalent to the
         cost price of the original car (having regard to the effects of
         inflation) and shall (subject as hereinafter provided) pay the testing
         taxation insurance premiums and the running expenses of such motor car
         including petrol lubrication maintenance and repairs

5.2      The Executive shall be permitted to use the said motor car on terms
         that he shall

         5.2.1    take good car of the car and ensure that it is kept in the
                  state and condition required by law and that the provisions
                  and conditions of any policy of insurance relating to it are
                  observed

         5.2.2    return the car (or such replacement as aforesaid) and its keys
                  to the Company's principal place of business immediately upon
                  the termination of his employment hereunder save that if the
                  Executive's employment is terminated pursuant to clause 2.1
                  above he shall be entitled to retain and use the car on the
                  like terms as provided in this clause 5 for the period to the
                  date when the notice of termination expires or would have
                  expired but for the provisions of clause 2.2

6.       Holidays and Holiday Pay
         ------------------------

6.1      The Executive shall be entitled (in addition to the normal Public and
         Bank Holidays) to twenty working days' holiday in each calendar year
         such holiday to be taken at a time or times convenient to the Company
         and to be agreed with the Group Chief Executive

6.2      On the cessation of the Executive's employment for whatever reason he
         shall be entitled to accrued holiday pay in lieu of holidays not taken
         at that date in direct proportion to his length of service hereunder

7.       Sickness
         --------

7.1      The Executive will notify or cause to be notified the Company as soon
         as he becomes unfit for work due to illness or injury. Failure to
         notify will entitle the Company at its absolute discretion to withhold
         payment of contractual and/or statutory sick pay

7.2      On each occasion the Executive is absent from work due to illness or
         injury he will provide evidence to the Company that he was unfit for
         work in accordance with the


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<PAGE>

         requirements of the Company from time to time. A doctor's certificate
         will be required in case of illness or injury lasting more than seven
         days

7.3      The Company shall be entitled during any period of incapacity of the
         Executive to require the Executive to undergo a medical examination by
         a doctor nominated by the Company which doctor shall be entitled to
         report the result of any such examination to the Company and to the
         Executive's own doctor

7.4      Subject to compliance with the foregoing provisions of this clause if
         the Executive is at any time prevented by illness or accident or any
         other medical incapacity from carrying out fully his duties hereunder
         his salary will not cease to be payable by reason only of his
         incapacity for work due to sickness or injury (unless the Executive's
         employment hereunder shall have been terminated). The Company shall be
         entitled to deduct from salary paid the maximum of any benefits to
         which the Executive shall be entitled under the current Social Security
         Acts whether or not he receives those benefits

7.5      The Executive shall during the continuance of his employment hereunder
         be entitled to participate in any private medical insurance scheme
         arranged by the Company for the benefit of employees on the terms from
         time to time agreed by the Company and the Company shall keep the
         Executive informed of the details of any such scheme currently
         applicable

8.       Pension
         -------

         The Executive shall during the continuance of his employment hereunder
         be entitled to have paid into a pension scheme nominated by him each
         year a sum equivalent to twelve per centum (12%) of his annual salary
         and the Executive shall contribute the equivalent of four per centum
         (4%) of his annual salary to such pension scheme. It shall be the
         responsibility of the Company to ensure that these contributions are
         made

9.       Confidentiality and Other Interests
         -----------------------------------

9.1      The Executive is aware that in the course of his employment hereunder
         he will have access to and be entrusted with information in respect of
         the business and finances of the Company and its dealings transactions
         and affairs all of which information is or may be confidential

9.2      The Executive shall not (except in the proper course of his duties
         hereunder) either during or at any time after the period of his
         employment hereunder divulge to any person whomsoever and shall use his
         best endeavours to prevent the publication or disclosure of and shall
         not use for his own purposes or for any purposes other than those of
         the Company and the Group any trade secret or process or any
         confidential information concerning the business or finances of the
         Company or the Group or any dealings transactions or affairs of any of
         them or any other information of a confidential character which may
         come to his knowledge during or in the course of his employment

10.      Termination of employment
         -------------------------

10.1     The Company may at any time by notice in writing to the Executive
         forthwith terminate his employment and the Executive shall have no
         claim against the Company in respect of such termination if the
         Executive shall

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<PAGE>

         10.1.1   commit any serious breach of this Agreement or continue (after
                  being warned in writing) any other breach of any of his
                  obligations (whether under this Agreement or otherwise) to the
                  Company or any Associated Company or

         10.1.2   be guilty of any fraud or gross default or misconduct in
                  connection with or affecting the business of the Company or
                  any Associated Company or be convicted of any criminal offence
                  (other than a motoring offence not resulting in a custodial
                  sentence) or

         10.1.3   be guilty of conduct tending to bring him the Company or any
                  Associated Company into disrepute or

         10.1.4   become bankrupt or compound or make any arrangement with his
                  creditors or

         10.1.5   become of unsound mind or a patient for the purpose of any
                  statute (or any part thereof) relating to mental health

10.2     The termination of the Executive's employment shall be without
         prejudice to any other remedy the Company may have if the termination
         is caused by the Executive's breach of any term of this Agreement

10.3     The rights of the Company under this clause are without prejudice to
         any other right it may have at law to terminate the Executive's
         employment

10.4     Upon the termination of the Executive's employment for whatever reason
         the Company will be entitled to deduct from any payments then due or
         becoming due to the Executive (whether in respect of any period before
         such termination or not) any monies which may then be or become due or
         may become due thereafter from the Executive to any company within the
         Group

10.5     In the event of this Agreement being determined by reason of the death
         of the Executive the personal representatives of the Executive shall be
         entitled to a proportion calculated pro rata temporis of his salary up
         to the date of such determination

10.6     If the employment of the Executive hereunder shall be terminated by
         reason of the liquidation of the Company for the purpose of
         amalgamation or reconstruction or as part of any arrangement for the
         amalgamation of its undertaking not involving liquidation and the
         Executive shall be offered employment with the amalgamated or
         reconstructed company on terms not less favourable to him than the
         terms of this Agreement then the Executive shall have no claim against
         the Company in respect of the termination of his employment by the
         Company hereunder

11.      Disciplinary Rules
         ------------------

11.1     The terms of this Agreement constitute the disciplinary rules to which
         the Executive is subject. If the Executive is dissatisfied with any
         disciplinary decision or has any grievance relating to his employment
         hereunder he should initially address himself to the Group Chief
         Executive for the time being of the Company or such other person as the
         Board shall from time to time direct in writing to the Executive. If
         after such initial action the Executive wishes to pursue the matter
         further he should refer the matter in writing to the Board



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<PAGE>

11.2     The Company reserves the right in any appropriate case to suspend the
         employment of the Executive with or without payment of remuneration. If
         the Executive's employment is terminated during or immediately
         following any period of suspension without remuneration the Executive
         shall not be entitled to receive remuneration in respect of the period
         of suspension unless the Board in its discretion otherwise resolves

12.      Particulars of Employment
         -------------------------

         The employment of the Executive hereunder shall also be subject to the
         terms set out in the Schedule which is added in accordance with the
         requirements of Section 1 of the Act

13.      Assignment
         ----------

13.1     The benefit and burden of this Agreement will devolve upon and be
         enforceable by and against the Company' successors and assigns

13.2     For the purposes of this Agreement the Company will be entitled to
         carry out its obligations as to payment of remuneration and otherwise
         through such one or more of the companies within the Group as the Board
         may from time to time expressly determine and the Company may enforce
         the provisions of this Agreement either directly as a party or as agent
         for and on behalf of any such company

13.3     In addition to the last preceding sub-clause the Company shall have the
         right at any time (without the consent of the Executive) to assign the
         employment of the Executive hereunder to any Associated Company and in
         the event of assignment:-

         (a)      the Company shall within 30 days give to the Executive written
                  notice of such assignment together with details of the
                  assignee; and

         (b)      the assignee shall thereafter be regarded as the employer for
                  the purposes of this Agreement; and

         (c)      the Executive shall continue his employment with the assignee
                  on terms no less favourable to him than the terms of this
                  Agreement and he shall have no claim against the Company or
                  the assignee in respect of the said agreement

13.4     The Company shall have the right at any time (without the consent of
         the Executive) to second the Executive to any Associated Company or to
         any other company in which from time the Company or any Associated
         Company shall have a shareholding (provided that, for the avoidance of
         doubt, such secondment carries a comparable degree of responsibility
         and status) and in the event of such secondment:-

         (a)      the Company shall within 30 days give to the Executive written
                  notice of such secondment together with details of the company
                  to which the Executive is to be seconded; and

         (b)      the Company shall for all purposes remain the employer of the
                  Executive

14.      General
         -------

14.1     Notwithstanding the termination or expiry of the Executive's employment
         hereunder the provisions of this Agreement shall remain in full force
         and effect in accordance with their terms for so long as may be
         necessary to give effect thereto



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<PAGE>

14.2     No amendment to this Agreement or other agreement between the Company
         and the Executive as to the terms of employment of the Executive shall
         be legally binding on either of them unless and until such amendment or
         agreement is confirmed in writing and signed by both the Executive and
         a duly authorised officer of the Company

14.3     Any notice required to be served hereunder may be served personally or
         by being sent by recorded delivery in the case of a notice to the
         Executive to his address mentioned above or his last known home address
         and any such notice shall be deemed to have been served at the time of
         delivery in the case of personal service or at the expiration of 48
         hours after it is posted

14.4     This Agreement shall be governed by English law which shall be the
         proper law thereof in all respects

IN WITNESS whereof the Company has caused its Common Seal to be hereunto affixed
and the Executive has hereunto set his hand and seal the day and year first
above written













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<PAGE>

                                    SCHEDULE
                                    --------

                        Statement of terms of employment
                        --------------------------------

1.       Amplification of terms of employment:

         (a)      Name of the employer:      FLEXTECH plc

         (b)      Address of the employer:   The Quadrangle Imperial Square
                                             Cheltenham Gloucestershire GL50 1YX

         (c)      Name of the Executive:     MARK WALTER LUIZ

         (d)      Address of the Executive:  165 Cranley Gardens  London  N10

         (e)      Date of commencement of
                  continuous  employment:   September 12th 1988

                  Any period of employment with a previous employer does not
                  count as part of the Executive's continuous period of
                  employment with the Company

         (f)      Remuneration - See Clause 4:(pound)130,000 per annum payable
                  in monthly instalments in arrears

         (g)      Notice - See Clause 2:

         (h)      Job Title: Chief Financial Officer and Company Secretary

2.       In accordance with Section 1(3) of the Act the following terms of the
         Executive's employment apply on the date of the Agreement to which this
         is a Schedule

         (a)      Hours of Work: There are no fixed hours of work - see clause 3
                  of the Agreement

         (b)      Holidays: See clause 6 of the Agreement

         (c)      Sickness or injury: See clause 7 of the Agreement

         (d)      Other benefits - See clauses 4, 5, 7, 8

3.       The following information is supplied pursuant to the Act and reflects
         the Company's current practice

         (a)      Disciplinary Rules. There is no formal disciplinary procedure
                  applicable to this employment. The Executive shall merely be
                  expected to exhibit a high standard of propriety in all his
                  dealings with and in the name of the Company and the
                  Associated Companies

         (b)      Grievance Procedure: See clause 11

         (c)      Appeals Procedure: As 3(b) above

         (d)      A Contracting-Out Certificate is in force in respect of this
                  employment


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<PAGE>

SIGNED by                  )
for and on behalf of       ) /s/ Flextech plc
FLEXTECH plc               )
in the presence of:        )






SIGNED by the said         )
MARK WALTER LUIZ           ) /s/ Mark Walter Luiz
in the presence of:        )

















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