The association of Fanconi's anemia (FA) and growth hormone (-gh) deficiency is not commonly reported. These children may have the typical features of the FA syndrome, or may exhibit much variability in clinical and hematological findings. In a single family, members may have FA with or without GH deficiency. The genetic basis for this heterogeneity is unknown. We describe here two siblings with FA, one of whom had dwarfism due to GH deficiency. Combined treatment with GH and androgen (oxymetholone) resulted in strikingly greater acceleration of growth than did the use of GH alone. Pancytopenia was not influenced by hormone therapy.