Serum proteins, vitamin B12 level, iron and iron-binding capacity, and marrow iron stores were evaluated in 58 patients with the anemia of chronic disorders. Excellent correlations were observed between levels of serum albumin and transferrin and the venous hematocrit value. There was no correlation between venous hematocrit value and the levels of serum iron, vitamin B12, or γ-globulin, nor was there any correlation between marrow iron stores and serum iron level or iron-binding capacity. The reduced levels of albumin and transferrin were similar to the previously reported reduction in circulating erythropoietin value. It is suggested that a relative impairment of protein synthesis is common to the decreases in albumin, transferrin, and erythropoietin levels seen in patients with chronic disorders and that this impairment is causally related to their anemias.