October 16, 1998

L.B. Foster Company
415 Holiday Drive
Pittsburgh, Pennsylvania 15220

                  Re:      Voluntary Investment Plan as Amended and
                           Restated and Retirement Savings Plan for Non-Union
                           Hourly Employees as Amended and Restated
                           2,000,000 Shares of Common Stock

Ladies and Gentlemen:

         We have acted as your counsel in connection with the registration  with
the Securities and Exchange Commission (the "Commission") of 2,000,000 shares of
your  Common  Stock,  $.01 par  value  per  share , (the  "Shares")  that may be
acquired under the subject Plans by participants in the Plans.

         In that connection,  we have examined  originals or copies certified or
otherwise  identified to our satisfaction of such documents,  corporate  records
and  other  instruments  as we have  deemed  necessary  or  appropriate  for the
purposes of this opinion. Based on the foregoing, we are of the opinion that the
Shares,  when issued or delivered,  and paid for, in accordance  with the Plans,
will have been  validly  issued  and will be fully  paid and  nonassessable.  In
rendering  this  opinion  we  have  of  course  assumed  that  the  certificates
evidencing the Shares will be properly executed and authenticated.

         We consent  to the filing of this  opinion  with the  Commission  as an
exhibit to the Registration Statement on Form S-8 for registration of the Shares
under the Securities Act of 1933, as amended.

                              Very truly yours,

                              /s/ Klett Lieber Rooney & Schorling
                              -------------------------------------
                              KLETT LIEBER ROONEY & SCHORLING,
                              a Professional Corporation

                                                                   Exhibit 5