In parallel with the escalating incidence of serious, invasive fungal infections in the immune-compromised host has been the development and use of new, potentially efficacious antifungal agents as well as recognition of both primary and secondary resistance to such drugs by the etiologic mycotic agents. These findings have generated considerable enthusiasm for a reproducible and standardized means for the laboratory evaluation of antifungal drugs. For over a decade, global investigations have ensued in the hope of generating laboratory methods analogous to those used for antibacterial drugs that may predict the optimal therapeutic choice for clinicians treating mycoses. This article reviews the background, history, and development of in vitro antifungal susceptibility efforts, details the problems inherent in this area of laboratory medicine/infectious diseases, and assesses the contemporary aspects of standardization.