A literature review was conducted to summarize information, particularly recently published, on the biology of Rafflesia. By far most of the recent papers on Rafflesia have named new species. Since 2002, ten species have been discovered in the Philippines compared to three species in Indonesia. Recent work also has explored phylogenetics (e.g. evolutionary history of the genus and of floral gigantism, horizontal transfer of genes and loss of the chloroplast genome) and anatomy (e.g. endophyte, flower development); other studies have focused on biochemistry. Unfortunately, we still know very little about the life cycle, biology and ecological relations of Rafflesia. Population declines have been noted as related to habitat destruction or natural disturbances but other times the cause(s) are unknown. Questions remain unanswered on its reproductive biology and on its population genetic structure and diversity. With changing climates, long-term population studies in relation to environmental parameters are needed for Rafflesia conservation.