The concept of treating presumed streptococcal pharyngitis prior to obtaining throat culture results remains controversial. We review the rationale for early treatment and the predictive ability of current techniques for rapidly estimating the probability of streptococcal pharyngitis. Decision analysis is combined with clinical and microscopic predictive tests to provide an approach for early treatment of presumed streptococcal pharyngitis. Our unified approach supports the treatment of presumed streptococcal pharyngitis prior to obtaining culture results when specific clinical or microscopic criteria are met.