Total of 240 day-old male broiler chicks were assigned to 3 treatments with 4 replicates of 20 chicks. The experimental period lasted six weeks. Birds were fed according to NRC recommendations. Treatment 2 employed phase feeding (PF) from 0 to 6 week of age using a series of six diets formulated to contain digestible lysine, methionine, and threonine requirements predicted by linear regression equations. Treatment 3 employed modified phase feeding (MPF). The birds were fed according to NRC recommendations from 0 to 3 wk of age followed by PF diets from 3 to 6 wk of age. At the end of the 6 wk growing period, there were no differences between the treatments in either growth performance or carcass composition.