Thirty-nine patients, 25 of whom were suffering from trauma, sepsis, or malignant disease, were studied prospectively to determine the immunologic value of improved protein-calorie balance in this setting. All were suffering from varying degrees of malnutrition, and 72% (P less than 0.05) of the patients with anergy-inducing disease processes were anergic at the time of evaluation. In the presence of disease-induced anergy, skin test reactivity was not helpful in measuring the therapeutic response to nutritional support; among severely wasted patients, significant elevations in absolute lymphocyte count and serum albumin suggest that these are useful parameters when following the severely wasted patient who has concomitant trauma, sepsis, or malignant disease.