We diagnosed Fanconi's anemia (FA) in a 34-year-old lady, daughter of consanguineous parents, from a small Southern Italian town. The patient was pancytopenic when she was 31, and was found to be aplastic at the age of 34. Spontaneous chromosomal breakages were not evident in peripheral blood lymphocyte cultures but the diepoxybutane (DEB) test, carried out during the aplastic phase, was clearly positive. Danazol treatment significantly improved her hematological condition, yielding a Hb peak value of 13.4 g/dL. Four years later moderate pancytopenia has recurred. This case demonstrates that even adult pancytopenic patients may have FA and that a test detecting chromosomal hypersensitivity to cross-linking agents is the only key to a correct diagnosis, which in turn is essential to avoid improper treatment.