Posaconazole is a new antifungal agent, which exhibits a broad spectrum of activity against fungi including Aspergillus terreus, some zygomycetes and dematiaceous fungi. Out of the group of triazole antifungal agents, it is the only compound for which interpretive breakpoints have not been established have not yet been established for Candida spp. As reliable breakpoints are useful in the practical management of patients with fungal infections, it is desirable to establish the same for all available substances. However, the underlying data of the existing breakpoints for other antifungal agents are of varying quality because of limited clinical data available. Furthermore, these breakpoints are not equally suitable for all testing methods available and they may not be suitable for all species to be tested. From the practical point of view, it is therefore important not only to establish breakpoints for the reference method but also for the inexpensive and easy to perform testing methods, which are suitable for smaller laboratories.