Anatomical observations have indicated a decrease of marrow cellularity with age, but these changes are not associated with anemia in the healthy geriatric patient. Aged patients with refractory anemia should be studied by utilizing red cell volume (MCV) and red cell heterogeneity (RDW). A classification with these indices initially can separate the anemias for a more fruitful investigation. By old age the anemias of hereditary red cell membrane or hemoglobin disorders should be known to the patient. In the absence of tumor, elderly patients have an increasing frequency of refractory anemias that can be called preleukemia or myelodysplastic syndrome. Morphological observations have emphasized the importance of abnormal megakaryocytes and platelets in all phases of preleukemia, and these cytologic changes should be used to guide the physician in the early diagnosis of the syndrome complex. This group of refractory anemias have a limited survival, but nonspecific marrow stimulation can be effective and should be tried. With a more complete classification of the chromosomal abnormalities in the myelodysplastic syndrome, a more accurate prognosis can be anticipated. The anemias of marrow aplasia and ineffective iron utilization (anemia of chronic disease) are found frequently in the elderly, and the physician may offer more effective therapy by an early diagnosis.