June 24, 1999



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

        Re:      1998 Long-Term Incentive Plan as Amended
                 and Restated (the "Plan")
                 450,000 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 450,000 shares of
your Common Stock, $.01 par value per share (the "Shares"), that may be acquired
under the Plan by participants in the Plan.

         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
provisions of the Plan, 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,  and to the reference to us under
"LEGAL OPINION" in the Prospectus.


                              Very truly yours,


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





                                                       Exhibit 5