Ciguatera poisoning results from the consumption of fish and marine invertebrates contaminated with lipid soluble toxins known as ciguatoxins (CTXs) that are produced by benthic dinoflagellates in the genera Gambierdiscus and Fukuyoa. Overall, 16 species of Gambierdiscus and three closely related Fukuyoa species are now recognized worldwide. Occurrence data clearly highlight the current geographical expansion of these organisms from tropical and sub-tropical waters to temperate-like areas, a likely consequence of climate change. Numerous studies have examined Gambierdiscus/Fukuyoa spp. in vitro growth responses under varying environmental factors. Results confirm that differences in both tolerance and optimum growth ranges exist not only across species, but across strains as well. Gambierdiscus/Fukuyoa spp. are the potential source of at least six families of cyclic polyether compounds whose contribution to ciguatera syndrome (except for CTXs) as well as ecological relevance remain to be ascertained. Factors governing toxinogenesis in these organisms are not well understood, but several studies have provided evidence that this functional trait may depend on a combination of abiotic and biotic (including genetic) factors. Despite the significant advances achieved in the understanding of this phenomenon, ciguatera incidents remain difficult to predict, and their recent expansion to novel areas continues to pose a serious threat to the public health, lifestyle and economy of world populations. Suggested areas for future research efforts will be discussed.