Phosphorus (P) is an indispensable mineral for poultry, and a failure to supply satisfactory amount of this nutrient in bird’s diet, leads to serious economic losses. Therefore, poultry nutritionists propose reasonable safety margin for this mineral in bird’s feed. Limited resources of phosphate have been discovered and mined consistently. And ultimately, future generations will face problems in obtaining enough P to exist. Being the third most costly dietary constituent, one of the main pollutants in bird’s excreta, P deserves exceptional concern in feed formulation to meet specific requirements of poultry. This book, therefore, presents basics and applications, by which, broiler feed formulators can exploit adaptation potential of modern broiler strains to cope with modest deficiency of nutrients and especially P. In addition, it would be valuable for broiler producers to lessen feed expenses, as well as, to minimize P release in surrounding environment devoid of any unfavorable effects on birds.