The present study was designed to test the comparative efficacy of cow's milk, a protein, vitamin and mineral mixture (PVM) and soybean textured vegetable protein (SOMOS) as supplements to maize meal porridge in the dietary treatment of children with protein energy malnutrition (PEM). Each diet was designed to provide approximately 480 kJ/kg with 2 g protein/kg from the test protein, and 1.8 g protein/kg from maize. Response to treatment was measured by loss of oedema, subsequent weight gain, rate of generation of serum albumin, and serum amino acid patterns. In 36 children studied to date the three dietary regimens all produced satisfactory rates of cure of PEM. The clinical and economic implications of these results are discussed.