The ability to unambiguously describe phenotypes for all human disease in a manner that is able to be used and understood by both humans and computers is a challenge that cuts across the entire Human Variome Project. This presentation was used as a discussion starter for the "Describing Phenotype" session at the 4th Biennial Meeting of the Human Variome Project Consortium. These session discussed the logistics of collection and reporting of phenotype, how phenotypes can be validated, as well as the ethics of reporting phenotype on publicly accessible databases.