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An extensive literature review was conducted to evaluate best management practices (BMPs) and for the agronomy, dairy, swine and poultry industries in the Chesapeake Bay watershed. This indepth evaluation will be applicable in developing new tributary strategies for further reducing nutrient loads from agriculture. Emphasis was placed on reviewing new technology for nitrogen and phosphorus agronomic BMPs and new manure management BMPs. Manure management BMPs included treatment and modifying poultry and animal diets to decrease manure nutrient excretion in the manure. Manure management practices that may effect the dairy industry in the Chesapeake Bay watershed include dietary manipulation to optimize amounts of rumen degradable protein and rumen nondegradable protein in cattle feed and use of low protein roughages such as corn silage or low protein concentrates. Dietary manipulation will reduce excretion of N in manure and reducing P levels in feed rations for high producing cows to about 0.40%. Feed modification in the swine industry has included adding phytase to the diet, formulating the crude protein according to requirements, incorporating non-starch polysaccharides in the diet to move N excreted in the feces and less in the urine and supplementing with synthetic amino acids. The manipulation of the pig's diet to reduce nutrient excretion is feasible and practical, but economics is still a major issue in using this technology. One of the major poultry industry issues in the watershed is the concentration of broiler production in some areas. The broiler diet can be modified to reduce the excretion of P. Two practices that are being used include adding phytase to the feed and using high available phosphorus corn in the diet. Alternative uses of manure is also an option.