According to the US Vital Health Statistics report, acute pharyngotonsillitis is responsible for more than 6 million office visits each year by children younger than 15 years of age. Approximately 30% of cases is of bacterial etiology and group A beta-hemolytic streptococci(GABHS) are responsible for most bacterial cases, although other pathogens, such as Neisseria gonorrhoeae, Arcanobacterium haemolyticum, Mycoplasma pneumoniae, and Chlamydia pneumoniae, may be the causative agents in sporadic cases. An accurate diagnosis of GABHS infection is important because it is the only common form of acute pharyngotonsillitis for which antibiotic therapy is definitely indicated. Effective antibacterial treatment can shorten the clinical course of GABHS pharyngotonsillitis, reduce the rate of transmission, and prevent suppurative and nonsuppurative complications, such as peritonsillar abscess and acute rheumatic fever.