• Objective: To assess the role of protein calorie malnutrition in continuous ambulatory peritoneal dialysis (CAPD) and the relevance of dialysis adequacy to patient nutritional well-being. • Data Sources: Peer-reviewed published literature pertaining to dietary intake, protein catabolism, and peritoneal losses in CAPD. • Data Synthesis: Protein calorie malnutrition, an independent risk factor of morbidity and mortality, is common. Etiology along with prevention and treatment involve multiple strategies. Loss of residual renal function, an important risk factor for reduced dietary protein intake and body composition, should be addressed with compensatory dialysis volume increase. • Conclusions: Although there is no single “gold standard” to define nutritional state, a large number of measures exist in conjunction with established criteria for malnutrition that can be integrated into routine screening programs. Prospective studies are needed to clarify the weak link between dialysis adequacy and nutrition. The use of intraperitoneal amino acids may provide a reliable means of increasing nitrogen input, but further work is required to evaluate the long-term benefit.