Growth performance of broiler chickens may be sub-optimal because starch is digested too rapidly and protein too slowly. This chapter reviews how a better understanding of digestive kinetics can address this challenge and contribute to least-cost formulation of broiler diets to enhance chicken-meat production. It begins by reviewing the process of protein and starch digestion. The chapter then reviews factors affecting digestion such as the speed of protein digestion and amino acid absorption, the more rapid intestinal uptake of non-bound methionine, as well as the role of slowly-digestible starch in promoting broiler growth performance. The chapter shows that accounting for these factors can significantly improve the efficiency of broiler diets.