there are four issues that affect the growth of metal and ceramic matrix composites. they are: 1) the lack of suitable fibers for specific applications; 2) incomplete understanding of interface phenomena and lack of suitable surface treatments for specific composite applications; 3) preform technology not well developed and; 4) economic considerations that underlie all of the above issues commercial fibers on the market today are in great need of improvement. fibers must be strong, have high modulus and have an interface designed to maximize axial toughness and transverse strength while still being affordable. a review of the various matrix/reinforcement systems and an analysis of the required developments for commercial viability is given. also presented are the requirements of the interface between metal and ceramic matrices and the fiber reinforcement for aluminum, nickel aluminides, titanium aluminides and ceramic matrices. current methods of preform fabrication are reviewed and directions for improvement will be discussed. (author abstract) 25 refs. in italian