There are several reasons why nutritionists focus on diet composition for broilers. Efficiency, optimal product quality, reducing the environmental pressure and optimizing broiler health and welfare are key factors. Knowledge about which raw materials can be used and how to combine these is very important. Opportunities to enhance broiler nutrition lay in the use of feed additives or new ingredients with some being recently implemented and others having future potential. Recommendations have been made based on specific genetic lines, but genetic lines have been adapted which will have an impact on the nutritional needs as will the sex of the birds or the production system. More recently it has been shown that amino acid recommendations based on performance not always match needs when considering broiler welfare. Finally, also particle size, feed structure and form are key factors as they not only influence the gastrointestinal tract development, intestinal microflora overall performanance.