The echinocandin drugs are potent inhibitors of glucan synthase and are the first class of antifungal agents to target the fungal cell wall. The three principal drugs, caspofungin, micafungin and anidulafungin are highly serum protein bound, and display favourable pharmacokinetic and pharmacodynamic properties, as well as an excellent safety profile. Although initially approved for salvage therapy for invasive aspergillosis, treatment regimens are still evolving. The echinocandin drugs are moderately fungistatic with Aspergillus spp. but their in vivo effectiveness appears to be derived from drug-induced enhancement of the local immune response. Drug resistance is a rare event that has been linked to changes in glucan synthase subunit Fks1p.