AbstractAdvancements in our understanding of amebiasis have been rapid over the decade that I have followed this field.″What was identified morphologically for years asEntamoeba histolyticahas been redescribed with modern techniques as a complex of two species, the commensal parasiteE. disparand the pathogenic parasiteE. histolyticathat is the cause of colitis and liver abscess. Antigen detection tests are now available for the rapid detection in stool of the pathogenic speciesE. histolytica.New understandings of the importance of luminal as well as tissue-active antimebic medications in the treatment of invasive disease have been reached. The groundwork is being laid for an understanding of the protective immune responses to infection, and at the lab bench DNA transfection of the parasite has opened studies of pathogenesis to genetic analysis. While necessarily an incomplete sketch of the field, I have attempted here to highlight some recent and important developments of interest to clinicians and microbiologists.