The in vitro fungicidal and fungistatic activities of terbinafine were compared with those of itraconazole and amphotericin B against Aspergillus (n=63) and Cladosporium (n=21) isolates. The broth macrodilution modification of NCCLS reference method for filamentous fungi (M38-P) was used to assess the minimum inhibitory concentrations (MICs). Our data show that the in vitro activities of terbinafine were comparable to those of itraconazole and amphotericin B against the Aspergillus spp and Cladosporium strains tested. Despite strain-dependent variabilities, in general, itraconazole's activity was similar to that of amphotericin B against strains of Aspergillus and Cladosporium. Our data suggest that terbinafine may be useful in the treatment of Aspergillus and Cladosporium infections.