EXHIBIT 5.1
(Allen & Gledhill Letterhead)
Allen & Gledhill
36 Robinson Road
#18-01 City House
Singapore 068877

October 13, 1998

Flextronics International Ltd.
514 Chai Chee Lane #04-13
1 Bedok Industrial Estate
Singapore 469029

Dear Sirs,

We  refer  to  the  Registration   Statement  on  Form  S-3  (the  "Registration
Statement") filed or to be filed by the Company with the Securities and Exchange
Commission on or about October 13th,  1998 in connection  with the  registration
under the Securities Act of 1933, as amended,  of 3,262,403  ordinary  shares of
S$0.01 each in the capital of the Company (the  "Ordinary  Shares") to which the
Registration  Statement relates (the  "Registration  Shares").  According to the
Registered Statement,  the Registration Shares were part of, and included in the
4,222,667 Ordinary Shares, which is the aggregate of: -

1.   303,288  Ordinary Shares allotted and issued pursuant to the acquisition by
     the Company of all of the outstanding  quotas of Conexao  Informatica Ltda.
     (the "Conexao Ordinary Shares");

2.   630,920 Ordinary Shares allotted and issued pursuant to (I) the acquisition
     by statutory merger of Altatron,  Inc.  ("Altatron")  through the merger of
     Altatron  with  and  into  FA  Acquisition   Corporation  (a   wholly-owned
     subsidiary of the Company),  and (ii) the  acquisition by the Company (or a
     subsidiary,  or subsidiaries,  of the Company designated by the Company) of
     all of the outstanding  membership  interests in Marathon Business Park LLC
     (the "Altatron Ordinary Shares");

3.   2,806,000  Ordinary  Shares allotted and issued pursuant to the acquisition
     by the Company of 92% of the outstanding  shares of Neutronics  Electronics
     Industries Holding A.G. (the "Neutronics Ordinary Shares");

4.   229,990  Ordinary Shares allotted and issued pursuant to the acquisition by
     Flextronics  International  (Sweden) AB ( a wholly-owned  subsidiary of the
     Company)  of  all  of  the  outstanding   shares  of  Energipilot  AB  (the
     "Energipilot Ordinary Shares"); and

5.   252,469  Ordinary Shares allotted and issued pursuant to the acquisition by
     statutory  merger of DTM Products,  Inc.  ("DTM") through the merger of DTM
     with and into CBJ One,  Inc. ( a  wholly-owned  subsidiary  of the Company)
     (the "DTM Ordinary Shares"),

the Conexao  Ordinary Shares,  Altatron  Ordinary  Shares,  Neutronics  Ordinary
Shares,  Energipilot  Ordinary  Shares,  and DTM Ordinary Shares are hereinafter
collectively  referred to as the  "Consideration  Ordinary  Shares",  previously
registered on Form S-1, Registration No. 333-53311.

As your Singapore counsel, we have examined the proceedings taken by the Company
in  connection  with the allotment  and issuance of the  Consideration  Ordinary
Shares.  We have also made such  other  examinations  of law and fact as we have
considered  necessary  in  order  to form a  basis  for  the  opinion  hereafter
expressed.

Based on the foregoing,  we are of the opinion that the  Consideration  Ordinary
Shares  allotted and issued by the Company,  and which are  represented by share
certificates  issued in  respect  of such  Consideration  Ordinary  Shares,  are
legally issued and fully-paid.

We  consent  to the  use of  this  opinion  as an  exhibit  to the  Registration
Statement  and  further  consent  to  all  references  to  us,  if  any,  in the
Registration Statement and any amendments thereto.

Yours faithfully